(fix) make sure to use crypt as the scheme for md5/sha256/sha512 (fixes #4137)

SoObjects/SOGo/LDAPSource.m

@@ -599,6 +599,13 @@ groupObjectClasses: (NSArray *) newGroupObjectClasses
       return nil;
     }
 
+  if ([_userPasswordAlgorithm caseInsensitiveCompare: @"md5-crypt"] == NSOrderedSame ||
+      [_userPasswordAlgorithm caseInsensitiveCompare: @"sha256-crypt"] == NSOrderedSame ||
+      [_userPasswordAlgorithm caseInsensitiveCompare: @"sha512-crypt"] == NSOrderedSame)
+    {
+      _userPasswordAlgorithm = @"crypt";
+    }
+
   return [NSString stringWithFormat: @"{%@}%@", _userPasswordAlgorithm, pass];
 }