--- multistep.module	2010-08-18 14:47:25.000000000 +0200
+++ multistep.module.filefield-working	2010-08-18 14:48:53.000000000 +0200
@@ -651,7 +651,14 @@
  */
 function _multistep_get_current_step($type) {
   $step = 1;
-  // This condition occurs if using AHAH to add another value for a multi-value field.
+  // This condition allows the Multistep module to work with filefields
+  if (arg(0) == 'filefield' && arg(1) == 'ahah') {
+    $type = arg(2);
+    $field = arg(3);
+    $step = _multistep_get_field_step($field, $type);
+    return $step;
+  }
+    // This condition occurs if using AHAH to add another value for a multi-value field.
   if (arg(1) == 'js_add_more') {
     $type = arg(2);
     $field = arg(3);