Index: image.php
===================================================================
--- image.php	(revision 23356)
+++ image.php	(working copy)
@@ -20,7 +20,7 @@
  * @param int $dst_h The destination height.
  * @param int $src_abs Optional. If the source crop points are absolute.
  * @param string $dst_file Optional. The destination file to write to.
- * @return string|WP_Error|false New filepath on success, WP_Error or false on failure.
+ * @return string|WP_Error New filepath on success, WP_Error on failure.
  */
 function wp_crop_image( $src, $src_x, $src_y, $src_w, $src_h, $dst_w, $dst_h, $src_abs = false, $dst_file = false ) {
 	$src_file = $src;
@@ -54,6 +54,9 @@
 	$dst_file = dirname( $dst_file ) . '/' . wp_unique_filename( dirname( $dst_file ), basename( $dst_file ) );
 
 	$result = $editor->save( $dst_file );
+	if ( is_wp_error( $result ) )
+		return $result;
+		
 	return $dst_file;
 }