diff --git a/SoObjects/SOGo/SOGoMailer.m b/SoObjects/SOGo/SOGoMailer.m
index f792669..c02bae4 100644
--- a/SoObjects/SOGo/SOGoMailer.m
+++ b/SoObjects/SOGo/SOGoMailer.m
@@ -129,6 +129,7 @@
   NSException *result = nil;
   NSRange r;
   unsigned int port;
+  SOGoSystemDefaults *sd;
 
   client = [NGSmtpClient smtpClient];
   host = smtpServer;
@@ -152,6 +153,26 @@
       if ([authenticationType isEqualToString: @"plain"])
         {
           login = [[authenticator userInContext: woContext] login];
+          sd = [SOGoSystemDefaults sharedSystemDefaults];
+          if ([sd enableDomainBasedUID]) 
+          {
+                //multidomain mode, login is uid@domainID -> change to uid@mailDomain if domainID found
+
+                NSArray *userparts;
+                userparts = [login componentsSeparatedByString: @"@"];
+                NSString *domainName = nil;
+
+                if ([userparts count] == 2)
+                {
+                   domainName = [[SOGoDomainDefaults defaultsForDomain: [userparts objectAtIndex: 1]] mailDomain];
+                   if ([domainName length]>0)
+                   {
+                    login = [NSString stringWithFormat: @"%@@%@", [userparts objectAtIndex: 0], domainName];
+                   }
+                }
+
+          }
+
           password = [authenticator passwordInContext: woContext];
           if ([login length] == 0
               || [login isEqualToString: @"anonymous"]