--- /home/takahide/debs/mantis/mantis-1.0.1/core/print_api.php	2006-02-03 12:56:33.000000000 +0900
+++ core/print_api.php	2006-05-03 02:14:35.715340115 +0900
@@ -37,7 +37,7 @@
 		$t_url = string_sanitize_url( $p_url );
 
 		# don't send more headers if they have already been sent (guideweb)
-		if ( ! headers_sent() ) {
+		if ( ! headers_sent( $t_file, $t_linenum ) ) {
 			header( 'Content-Type: text/html; charset=' . lang_get( 'charset' ) );
 
 			if ( ON == $t_use_iis ) {
@@ -46,6 +46,7 @@
 				header( "Location: $t_url" );
 			}
 		} else {
+                        print "ERROR: Redirection failed. May be problem is in line $t_linenum of $t_file .";
 			return false;
 		}