Index: branches/RC/core/units/admin/admin_events_handler.php
===================================================================
diff -u -r9521 -r9542
--- branches/RC/core/units/admin/admin_events_handler.php	(.../admin_events_handler.php)	(revision 9521)
+++ branches/RC/core/units/admin/admin_events_handler.php	(.../admin_events_handler.php)	(revision 9542)
@@ -100,11 +100,17 @@
 					// size is described in structure -> add formatter
 					$field_options['formatter'] = 'kFormatter';
 					$field_options['format'] = '%01.'.$regs[1].'f';
-					$default_value = 0;
+					if ($field_info['Null'] != 'YES') {
+						// null fields, will most likely have NULL as default value
+						$default_value = 0;
+					}
 				}
 				else {
 					// no size information, just convert to float
-					$default_value = (float)$default_value;
+					if ($field_info['Null'] != 'YES') {
+						// null fields, will most likely have NULL as default value
+						$default_value = (float)$default_value;
+					}
 				}
 			}