fixed null pointer error when no options are selected.

multiselect.module

@@ -207,12 +207,14 @@ function multiselect_fix_selected($field, $edit)
     $field['selected']['#options'] =  array();
     $field['unselected']['#options'] =  $field['#all_options'];
     
+    if ( !is_null($selected) ){
       foreach( $selected as $selected_nid )
       {
         $field['selected']['#options'][$selected_nid] = $field['#all_options'][$selected_nid];
         unset($field['unselected']['#options'][$selected_nid]);
       }
     }
+  }
   
   return $field;
 }