diff -Nuar -x '*.orig' openldap-2.4.31.orig/configure openldap-2.4.31/configure
--- openldap-2.4.31.orig/configure	2012-07-19 14:40:03.439918158 +0200
+++ openldap-2.4.31/configure	2012-07-19 14:41:49.145415399 +0200
@@ -780,6 +780,7 @@
 SLAPD_NDB_LIBS
 BDB_LIBS
 SLAPD_LIBS
+BUILD_TRANSLOG
 LDAP_LIBS
 BUILD_VALSORT
 BUILD_UNIQUE
@@ -1708,6 +1709,7 @@
     --enable-translucent  Translucent Proxy overlay no|yes|mod [no]
     --enable-unique       Attribute Uniqueness overlay no|yes|mod [no]
     --enable-valsort      Value Sorting overlay no|yes|mod [no]
+    --enable-translog	  Transactions Log overlay no|yes|mod [no]
 
 Library Generation & Linking Options
   --enable-static[=PKGS]  build static libraries [default=yes]
@@ -3640,6 +3642,28 @@
 fi
 # end --with-cyrus_sasl
 
+# OpenLDAP --enable-translog
+	# Check whether --enable-translog or --disable-translog was given.
+if test "${enable_translog+set}" = set; then
+  enableval="$enable_translog"
+
+	ol_arg=invalid
+	for ol_val in no yes mod ; do
+		if test "$enableval" = "$ol_val" ; then
+			ol_arg="$ol_val"
+		fi
+	done
+	if test "$ol_arg" = "invalid" ; then
+		{ { echo "$as_me:$LINENO: error: bad value $enableval for --enable-translog" >&5
+echo "$as_me: error: bad value $enableval for --enable-translog" >&2;}
+   { (exit 1); exit 1; }; }
+	fi
+	ol_enable_translog="$ol_arg"
+
+else
+  	ol_enable_translog="no"
+fi; # end --enable-translog
+
 # OpenLDAP --with-fetch
 
 # Check whether --with-fetch was given.
@@ -4423,7 +4447,8 @@
 	syncprov \
 	translucent \
 	unique \
-	valsort"
+	valsort \
+	translog"
 
 # Check whether --enable-xxslapoverlays was given.
 if test "${enable_xxslapoverlays+set}" = set; then :
@@ -4890,6 +4915,29 @@
 
 # end --enable-valsort
 
+# OpenLDAP --enable-translog
+
+	# Check whether --enable-translog or --disable-translog was given.
+if test "${enable_translog+set}" = set; then
+  enableval="$enable_translog"
+
+	ol_arg=invalid
+	for ol_val in no yes mod ; do
+		if test "$enableval" = "$ol_val" ; then
+			ol_arg="$ol_val"
+		fi
+	done
+	if test "$ol_arg" = "invalid" ; then
+		{ { echo "$as_me:$LINENO: error: bad value $enableval for --enable-translog" >&5
+echo "$as_me: error: bad value $enableval for --enable-translog" >&2;}
+   { (exit 1); exit 1; }; }
+	fi
+	ol_enable_translog="$ol_arg"
+
+else
+  	ol_enable_translog=${ol_enable_overlays:-no}
+fi;
+# end --enable-translog
 
 # Check whether --enable-xxliboptions was given.
 if test "${enable_xxliboptions+set}" = set; then :
@@ -5113,6 +5161,7 @@
 BUILD_TRANSLUCENT=no
 BUILD_UNIQUE=no
 BUILD_VALSORT=no
+BUILD_TRANSLOG=no
 
 SLAPD_STATIC_OVERLAYS=
 SLAPD_DYNAMIC_OVERLAYS=
@@ -24710,6 +24759,22 @@
 
 fi
 
+if test "$ol_enable_translog" != no ; then
+	BUILD_TRANSLOG=$ol_enable_translog
+	if test "$ol_enable_translog" = mod ; then
+		MFLAG=SLAPD_MOD_DYNAMIC
+		SLAPD_DYNAMIC_OVERLAYS="$SLAPD_DYNAMIC_OVERLAYS translog.la"
+	else
+		MFLAG=SLAPD_MOD_STATIC
+		SLAPD_STATIC_OVERLAYS="$SLAPD_STATIC_OVERLAYS translog.o"
+	fi
+
+cat >>confdefs.h <<_ACEOF
+#define SLAPD_OVER_TRANSLOG $MFLAG
+_ACEOF
+
+fi
+
 if test "$ol_enable_valsort" != no ; then
 	BUILD_VALSORT=$ol_enable_valsort
 	if test "$ol_enable_valsort" = mod ; then
diff -Nuar -x '*.orig' openldap-2.4.31.orig/configure.in openldap-2.4.31/configure.in
--- openldap-2.4.31.orig/configure.in	2012-07-19 14:40:03.415919250 +0200
+++ openldap-2.4.31/configure.in	2012-07-19 14:41:49.145415399 +0200
@@ -355,7 +355,8 @@
 	syncprov \
 	translucent \
 	unique \
-	valsort"
+	valsort \
+	translog"
 
 AC_ARG_ENABLE(xxslapoverlays,[
 SLAPD Overlay Options:])
@@ -402,6 +403,8 @@
 	no, [no yes mod], ol_enable_overlays)
 OL_ARG_ENABLE(valsort,[    --enable-valsort      Value Sorting overlay],
 	no, [no yes mod], ol_enable_overlays)
+OL_ARG_ENABLE(translog,[    --enable-translog      Transactions Log overlay],
+	no, [no yes mod], ol_enable_overlays)
 
 dnl ----------------------------------------------------------------
 AC_ARG_ENABLE(xxliboptions,[
@@ -570,6 +573,7 @@
 BUILD_TRANSLUCENT=no
 BUILD_UNIQUE=no
 BUILD_VALSORT=no
+BUILD_TRANSLOG=no
 
 SLAPD_STATIC_OVERLAYS=
 SLAPD_DYNAMIC_OVERLAYS=
@@ -3043,6 +3047,18 @@
 	AC_DEFINE_UNQUOTED(SLAPD_OVER_VALSORT,$MFLAG,[define for Value Sorting overlay])
 fi
 
+if test "$ol_enable_translog" != no ; then
+	BUILD_TRANSLOG=$ol_enable_translog
+	if test "$ol_enable_translog" = mod ; then
+		MFLAG=SLAPD_MOD_DYNAMIC
+		SLAPD_DYNAMIC_OVERLAYS="$SLAPD_DYNAMIC_OVERLAYS translog.la"
+	else
+		MFLAG=SLAPD_MOD_STATIC
+		SLAPD_STATIC_OVERLAYS="$SLAPD_STATIC_OVERLAYS translog.o"
+	fi
+	AC_DEFINE_UNQUOTED(SLAPD_OVER_TRANSLOG,$MFLAG,[define for Transactions Log overlay])
+fi
+
 if test "$ol_enable_rewrite" != no ; then
 	AC_DEFINE(ENABLE_REWRITE,1,[define to enable rewriting in back-ldap and back-meta])
 	BUILD_REWRITE=yes
@@ -3120,6 +3136,7 @@
   AC_SUBST(BUILD_TRANSLUCENT)
   AC_SUBST(BUILD_UNIQUE)
   AC_SUBST(BUILD_VALSORT)
+  AC_SUBST(BUILD_TRANSLOG)
 
 AC_SUBST(LDAP_LIBS)
 AC_SUBST(SLAPD_LIBS)
diff -Nuar -x '*.orig' openldap-2.4.31.orig/include/portable.hin openldap-2.4.31/include/portable.hin
--- openldap-2.4.31.orig/include/portable.hin	2012-07-19 14:40:03.415919250 +0200
+++ openldap-2.4.31/include/portable.hin	2012-07-19 14:41:49.145415399 +0200
@@ -1026,6 +1026,9 @@
 /* define for Value Sorting overlay */
 #undef SLAPD_OVER_VALSORT
 
+/* define for Translog overlay */
+#undef SLAPD_OVER_TRANSLOG
+
 /* define to support PASSWD backend */
 #undef SLAPD_PASSWD
 
diff -Nuar -x '*.orig' openldap-2.4.31.orig/servers/slapd/overlays/Makefile.in openldap-2.4.31/servers/slapd/overlays/Makefile.in
--- openldap-2.4.31.orig/servers/slapd/overlays/Makefile.in	2012-07-19 14:40:03.379921977 +0200
+++ openldap-2.4.31/servers/slapd/overlays/Makefile.in	2012-07-19 14:41:49.149415346 +0200
@@ -33,7 +33,8 @@
 	syncprov.c \
 	translucent.c \
 	unique.c \
-	valsort.c
+	valsort.c \
+	translog.c
 OBJS = statover.o \
 	@SLAPD_STATIC_OVERLAYS@ \
 	overlays.o
@@ -125,6 +126,9 @@
 valsort.la : valsort.lo
 	$(LTLINK_MOD) -module -o $@ valsort.lo version.lo $(LINK_LIBS)
 
+translog.la : translog.lo
+	$(LTLINK_MOD) -module -o $@ translog.lo version.lo $(LINK_LIBS)
+
 install-local:	$(PROGRAMS)
 	@if test -n "$?" ; then \
 		$(MKDIR) $(DESTDIR)$(moduledir); \
diff -Nuar -x '*.orig' openldap-2.4.31.orig/servers/slapd/overlays/translog.c openldap-2.4.31/servers/slapd/overlays/translog.c
--- openldap-2.4.31.orig/servers/slapd/overlays/translog.c	1970-01-01 01:00:00.000000000 +0100
+++ openldap-2.4.31/servers/slapd/overlays/translog.c	2012-07-19 14:41:49.149415346 +0200
@@ -0,0 +1,322 @@
+/* translog.c - log modifications for replication purposes */
+
+#include "portable.h"
+
+#ifdef SLAPD_OVER_TRANSLOG
+
+#include <stdio.h>
+#include <unistd.h>
+#include <ac/string.h>
+#include <ac/ctype.h>
+#include "slap.h"
+
+//#define O_DEBUG		/* enable debug messages */
+
+typedef struct translog_data {
+	ldap_pvt_thread_mutex_t ad_mutex;
+	char *ad_logfile;
+} translog_data;
+
+static const char LAST_ID[] = "/var/lib/univention-ldap/last_id";
+static const char LAST_ID_TMP[] = "/var/lib/univention-ldap/last_id.new";
+static const char TRANSACTION[] = "/var/lib/univention-ldap/notify/transaction";
+
+static FILE* fopen_lock(const char *name, const char *type, FILE **l_file)
+{
+	char buf[PATH_MAX];
+	FILE *file;
+	int fd;
+
+	if (snprintf(buf, sizeof(buf), "%s.lock", name) >= sizeof(buf))
+		return NULL;
+
+	if ((*l_file = fopen(buf, type)) == NULL)
+		return NULL;
+
+	fd = fileno(*l_file);
+	lockf(fd, F_LOCK, 0);
+
+	if ((file = fopen(name, type)) == NULL) {
+		fclose(*l_file);
+		*l_file  = NULL;
+	}
+
+	return file;
+}
+
+static int fclose_lock(FILE **file, FILE **l_file)
+{
+	int ret = 0;
+
+	if (*file != NULL) {
+		ret = fclose(*file);
+		*file = NULL;
+	}
+
+	if (*l_file != NULL) {
+		fclose(*l_file);
+		*l_file = NULL;
+	}
+
+	return ret;
+}
+
+static long from_lastid()
+{
+	/* if the file /var/lib/univention-ldap/last_id exists, we read the last id
+	 * from this file
+	 */
+	FILE *f;
+	long id = -1;
+
+	if ((f = fopen(LAST_ID, "r")) != NULL) {
+		int n = fscanf(f, "%ld", &id);
+		fclose(f);
+
+		if (n != 1)
+			Debug(LDAP_DEBUG_ANY, "OVER: Failed to parse %s\n", LAST_ID, 0, 0);
+	}
+
+	return id;
+}
+
+static long from_translog(const char *filename)
+{
+	FILE *f;
+	long off = 2;
+	int c;
+	long id = -1;
+
+	if ((f = fopen(filename, "r")) == NULL) {
+		Debug( LDAP_DEBUG_ANY, "OVER: unable to open file %s\n", filename, 0, 0);
+		return -1;
+	}
+
+	do {
+		off++;
+		if (!fseek(f, -off, SEEK_END))
+			Debug(LDAP_DEBUG_ANY, "OVER: seek failed on %s\n", filename, 0, 0);
+		c = fgetc(f);
+	} while (c != '\n' && c != EOF && ftell(f) != 1);
+
+	if (c == EOF) {
+		/* emty file */
+		id = 0;
+	} else {
+		if (ftell(f) == 1) {
+			/* only one entry */
+			if (fseek(f, 0, SEEK_SET))
+				Debug(LDAP_DEBUG_ANY, "OVER: seek failed on %s\n", filename, 0, 0);
+		}
+		int n = fscanf(f, "%ld", &id);
+		if (n != 1)
+			Debug(LDAP_DEBUG_ANY, "OVER: Failed to parse %s at %ld\n", filename, off, 0);
+	}
+
+	fclose(f);
+	return id;
+}
+
+static long get_last_id(Operation *op)
+{
+	/* Get the last used Transaction ID from Transaction-Log file
+	 * Returns:
+	 * 	-1 und errors
+	 * 	0 if Transaction-Log file is empty
+	 * 	last Transaction ID if Transaction-Log file is nonempty
+	 */
+	long id;
+
+	Debug( LDAP_DEBUG_TRACE, "OVER: get_last_id\n", 0, 0, 0);
+
+	id = from_lastid();
+	if (id >= 1)
+		return id;
+
+	/* File must be locked to prevent UDN from renaming it underneth */
+	slap_overinst *on = (slap_overinst *)op->o_bd->bd_info;
+	translog_data *ad = on->on_bi.bi_private;
+	id = from_translog(ad->ad_logfile);
+	if (id >= 1)
+		return id;
+
+	id = from_translog(TRANSACTION);
+	return id;
+}
+
+static int translog_response(Operation *op, SlapReply *rs) {
+	/* Handel all requests and responses from and to database backend
+	 * Returns:
+	 * 	SLAP_CB_CONTINUE in all cases
+	 */
+	slap_overinst *on = (slap_overinst *)op->o_bd->bd_info;
+	translog_data *ad = on->on_bi.bi_private;
+	FILE *file, *l_file;
+	char what;
+	long lastid = -1;
+	int failure = 0;
+
+	if ( rs->sr_err != LDAP_SUCCESS ) {
+		Debug( LDAP_DEBUG_TRACE, "OVER: rs->sr_err != LDAP_SUCCESS on \"%s\" ERR: 0x%02x\n", op->o_req_dn.bv_val, rs->sr_err, 0 );
+		return SLAP_CB_CONTINUE;
+	}
+
+	if ( !op->o_bd || !ad->ad_logfile ) {
+		Debug( LDAP_DEBUG_TRACE, "OVER: BackendDB or logfile not specified\n", 0, 0, 0 );
+		return SLAP_CB_CONTINUE;
+	}
+
+	switch(op->o_tag) {
+		case LDAP_REQ_MODRDN:	what = 'r';	break; /* 0x6cU == LDAP_REQ_MODDN == LDAP_REQ_RENAME */
+		case LDAP_REQ_DELETE:	what = 'd';	break; /* 0x4aU */
+		case LDAP_REQ_ADD:		what = 'a';	break; /* 0x68U */
+		case LDAP_REQ_MODIFY:	what = 'm';	break; /* 0x66U */
+		case LDAP_REQ_SEARCH:	return SLAP_CB_CONTINUE; /* 0x63U get rid of search debug messages */
+		default:
+			Debug( LDAP_DEBUG_TRACE, "OVER: SWITCH(o_tag) default, case was: \"%lu\"\n", (unsigned long) op->o_tag, 0, 0 );
+			return SLAP_CB_CONTINUE;
+	}
+
+	ldap_pvt_thread_mutex_lock(&ad->ad_mutex);
+
+	if ((file = fopen_lock(ad->ad_logfile, "a", &l_file)) == NULL) {
+		Debug( LDAP_DEBUG_ANY, "OVER: Could not open translog file %s\n", ad->ad_logfile, 0, 0 );
+
+		ldap_pvt_thread_mutex_unlock(&ad->ad_mutex);
+		return SLAP_CB_CONTINUE;
+	}
+
+	lastid = get_last_id(op);
+	if ( lastid > -1 ) {
+		Debug( LDAP_DEBUG_TRACE, "OVER: Found ID \"%ld\"\n", lastid, 0, 0 );
+		failure |= fprintf(file, "%ld %s %c\n", ++lastid, op->o_req_dn.bv_val, what) <= 0;
+		if ( what == 'r' && op->orr_newSup ) {
+			/* print newsuperior as add in translog file */
+			failure |= fprintf(file, "%ld %s,%s a\n", ++lastid, op->orr_newrdn.bv_val, op->orr_newSup->bv_val) <= 0;
+		} else if ( what == 'r' ) {
+			struct berval   pdn;
+			dnParent( &op->o_req_dn, &pdn );
+			failure |= fprintf(file, "%ld %s,%s a\n", ++lastid, op->orr_newrdn.bv_val, pdn.bv_val) <= 0;
+		}
+	} else {
+		Debug( LDAP_DEBUG_ANY, "OVER: Could not find last ID, lastid seems to be: \"%ld\"\n", lastid, 0, 0 );
+		failure |= fprintf(file, "<TransID> %s %c\n", op->o_req_dn.bv_val, what) <= 0;
+		if ( what == 'r' && op->orr_newSup ) {
+			/* print newsuperior as add in translog file */
+			failure |= fprintf(file, "<TransID> %s,%s a\n", op->orr_newrdn.bv_val, op->orr_newSup->bv_val) <= 0;
+		} else if ( what == 'r' ) {
+			struct berval   pdn;
+			dnParent( &op->o_req_dn, &pdn );
+			failure |= fprintf(file, "<TransID> %s,%s a\n", op->orr_newrdn.bv_val, pdn.bv_val) <= 0;
+		}
+	}
+
+	failure |= fclose_lock(&file, &l_file) != 0;
+	if (failure)
+		Debug(LDAP_DEBUG_ANY, "OVER: Could not append file %s\n", ad->ad_logfile, 0, 0);
+
+	if ((file = fopen(LAST_ID_TMP, "w")) == NULL ||
+		fprintf(file, "%ld", lastid) <= 0 ||
+		!fclose(file)) {
+		Debug(LDAP_DEBUG_ANY, "OVER: Could not write file %s\n", LAST_ID_TMP, 0, 0);
+	} else {
+		if (rename(LAST_ID_TMP, LAST_ID))
+			Debug(LDAP_DEBUG_ANY, "OVER: Could not rename file %s\n", LAST_ID_TMP, 0, 0);
+	}
+
+#ifdef O_DEBUG
+	/* Test if the entry is in backend allready */
+	int rc;
+	Entry *e;
+	/* set "real" backend as next backend */
+	op->o_bd->bd_info = on->on_info->oi_orig;
+	rc = be_entry_get_rw( op, &op->o_req_ndn, NULL, NULL, 0, &e );
+	Debug( LDAP_DEBUG_TRACE, "OVER: Fetched Object, returncode was \"%d\"\n", rc, 0, 0);
+	if ( e ) {
+		Debug( LDAP_DEBUG_TRACE, "OVER: Fetched Object \"%s\"\n", e->e_ndn, 0, 0);
+	}
+	op->o_bd->bd_info = (BackendInfo *)on;
+#endif
+
+	ldap_pvt_thread_mutex_unlock(&ad->ad_mutex);
+	return SLAP_CB_CONTINUE;
+}
+
+static slap_overinst translog;
+
+static int translog_db_init( BackendDB *be ) {
+	Debug( LDAP_DEBUG_TRACE, "OVER: db_init\n", 0, 0, 0 );
+
+	slap_overinst *on = (slap_overinst *)be->bd_info;
+	translog_data *ad = ch_calloc(1, sizeof(translog_data));
+
+	on->on_bi.bi_private = ad;
+	ldap_pvt_thread_mutex_init( &ad->ad_mutex );
+	return 0;
+}
+
+static int translog_db_close( BackendDB *be ) {
+	Debug( LDAP_DEBUG_TRACE, "OVER: db_close\n", 0, 0, 0 );
+
+	slap_overinst *on = (slap_overinst *)be->bd_info;
+	translog_data *ad = on->on_bi.bi_private;
+
+	free( ad->ad_logfile );
+	ad->ad_logfile = NULL;
+	return 0;
+}
+
+static int translog_db_destroy( BackendDB *be ) {
+	Debug( LDAP_DEBUG_TRACE, "OVER: db_destroy\n", 0, 0, 0 );
+
+	slap_overinst *on = (slap_overinst *)be->bd_info;
+	translog_data *ad = on->on_bi.bi_private;
+
+	ldap_pvt_thread_mutex_destroy( &ad->ad_mutex );
+	free( ad );
+	return 0;
+}
+
+static int translog_config( BackendDB *be, const char *fname, int lineno, int argc, char **argv ) {
+	slap_overinst *on = (slap_overinst *) be->bd_info;
+	translog_data *ad = on->on_bi.bi_private;
+
+	Debug( LDAP_DEBUG_CONFIG|LDAP_DEBUG_TRACE, "OVER: Configuring Translog Overlay\n", 0, 0, 0 );
+
+	/* log file */
+	if ( strcasecmp( argv[0], "translog" ) == 0 ) {
+		if ( argc < 2 ) {
+			Debug( LDAP_DEBUG_ANY, "%s: line %d: missing filename in \"translog <filename>\" line\n", fname, lineno, 0 );
+			return(1);
+		}
+		Debug(LDAP_DEBUG_CONFIG, "OVER: Configured Translog Overlay to use file \"%s\"\n", argv[1], 0, 0);
+
+		/* save filename in translog_data */
+		ad->ad_logfile = ch_strdup( argv[1] );
+		return 0;
+	}
+	return SLAP_CONF_UNKNOWN;
+}
+
+int translog_init() {
+	Debug( LDAP_DEBUG_TRACE, "OVER: Loading Translog Overlay\n", 0, 0, 0 );
+
+	translog.on_bi.bi_type = "translog";
+	translog.on_bi.bi_db_init = translog_db_init;
+	translog.on_bi.bi_db_config = translog_config;
+	translog.on_bi.bi_db_close = translog_db_close;
+	translog.on_bi.bi_db_destroy = translog_db_destroy;
+	translog.on_response = translog_response;
+
+	return overlay_register(&translog);
+}
+
+#if SLAPD_OVER_TRANSLOG == SLAPD_MOD_DYNAMIC
+int
+init_module( int argc, char *argv[] )
+{
+	return translog_init();
+}
+#endif
+
+#endif /* SLAPD_OVER_TRANSLOG */