Index: functions.php
===================================================================
--- functions.php	(revision 15088)
+++ functions.php	(working copy)
@@ -282,7 +282,7 @@
  * @return string Excerpt with a pretty "Continue Reading" link
  */
 function twentyten_custom_excerpt_more( $output ) {
-	if ( has_excerpt() ) {
+	if ( has_excerpt() && ! is_attachment() ) {
 		$output .= twentyten_continue_reading_link();
 	}
 	return $output;