diff --git a/print.module b/print.module
index 8bd3fc47809fcc01ae67e1f4bb30142c94a2d893..e29ee1ccf459254cc014bfe363d94f7050d4b566 100644
--- a/print.module
+++ b/print.module
@@ -536,7 +536,13 @@ function print_rewrite_urls($matches) {
           $clean_url = (bool)variable_get('clean_url', '0');
           if (substr($url, 0, 1) == "/") {
             // If it starts with '/' just append it to the server name
-            $server = substr($base_url, 0, strpos($base_url, '/', 7));
+            $max = strpos($base_url, '/', 7);
+            if ($max === false) {
+              $server = $base_url;
+            }
+            else {
+              $server = substr($base_url, 0, $max);
+            }
             $newurl = $server .'/'. trim(urldecode($url), "/");
           }
           elseif ((!$clean_url) && (preg_match("/^[index.php]?\?q=.*/i", $url))) {