@@ -, +, @@ 
---
 .../modules/univention/s4connector/s4/__init__.py  | 31 ++++++++++++----------
 1 file changed, 17 insertions(+), 14 deletions(-)
--- a/services/univention-s4-connector/modules/univention/s4connector/s4/__init__.py	
+++ a/services/univention-s4-connector/modules/univention/s4connector/s4/__init__.py	
@@ -39,6 +39,7 @@ import string
 import re
 import sys
 import time
+import calendar
 import types
 import array
 import univention.uldap
@@ -215,26 +216,28 @@ def encode_s4_resultlist(s4_resultlist):
 	return s4_resultlist
 
 
-def unix2s4_time(l):
-	d = 116444736000000000L  # difference between 1601 and 1970
-	return long(time.mktime(time.gmtime(time.mktime(time.strptime(l, "%Y-%m-%d")) + 90000))) * 10000000 + d  # 90000s are one day and one hour
+def samba2s4_time(unix_ts):
+	delta = 116444736000000000L  # difference between 1601 and 1970
+	as_nanoseconds = unix_ts * 10000000
+	return as_nanoseconds + delta
 
 
-def s42unix_time(l):
-	d = 116444736000000000L  # difference between 1601 and 1970
-	return time.strftime("%d.%m.%y", time.gmtime((l - d) / 10000000))
+def s42samba_time(s4_ts):
+	delta = 116444736000000000L  # difference between 1601 and 1970
+	if s4_ts == 0:
+		return 0
+	nanoseconds_since_epoch = s4_ts - delta
+	return nanoseconds_since_epoch / 10000000
 
 
-def samba2s4_time(l):
-	d = 116444736000000000L  # difference between 1601 and 1970
-	return long(time.mktime(time.localtime(l))) * 10000000 + d
+def unix2s4_time(iso_date):
+	since_epoch = calendar.timegm(time.strptime(iso_date, '%Y-%m-%d'))
+	return samba2s4_time(since_epoch)
 
 
-def s42samba_time(l):
-	if l == 0:
-		return l
-	d = 116444736000000000L  # difference between 1601 and 1970
-	return long(((l - d)) / 10000000)
+def s42unix_time(s4_ts):
+	since_epoch = s42samba_time(s4_ts)
+	return time.strftime('%Y-%m-%d', time.gmtime(since_epoch))
 
 # mapping funtions
 
-- 
---
 .../modules/univention/s4connector/s4/__init__.py                | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)
--- a/services/univention-s4-connector/modules/univention/s4connector/s4/__init__.py	
+++ a/services/univention-s4-connector/modules/univention/s4connector/s4/__init__.py	
@@ -2164,7 +2164,8 @@ class s4(univention.s4connector.ucs):
 				# user enabled in UCS -> change
 				ucs_admin_object['disabled'] = 'all'
 				modified = 1
-		if 'accountExpires' in ldap_object_s4 and (long(ldap_object_s4['accountExpires'][0]) == long(9223372036854775807) or ldap_object_s4['accountExpires'][0] == '0'):
+		account_expires = long(ldap_object_s4['accountExpires'][0])
+		if 'accountExpires' in ldap_object_s4 and account_expires in (9223372036854775807, 0):
 			# s4 account not expired
 			if ucs_admin_object['userexpiry']:
 				# ucs account expired -> change
@@ -2172,11 +2173,11 @@ class s4(univention.s4connector.ucs):
 				modified = 1
 		else:
 			# s4 account expired
-			ud.debug(ud.LDAP, ud.INFO, "sync account_expire:      s4time: %s    unixtime: %s" % (long(ldap_object_s4['accountExpires'][0]), ucs_admin_object['userexpiry']))
+			ud.debug(ud.LDAP, ud.INFO, "sync account_expire:      s4time: %s    unixtime: %s" % (account_expires, ucs_admin_object['userexpiry']))
 
-			if s42unix_time(long(ldap_object_s4['accountExpires'][0])) != ucs_admin_object['userexpiry']:
+			if s42unix_time(account_expires) != ucs_admin_object['userexpiry']:
 				# ucs account not expired -> change
-				ucs_admin_object['userexpiry'] = s42unix_time(long(ldap_object_s4['accountExpires'][0]))
+				ucs_admin_object['userexpiry'] = s42unix_time(account_expires)
 				modified = 1
 
 		if modified:
--