diff --git a/i.php b/i.php
index 333c25baa..a45daa091 100644
--- a/i.php
+++ b/i.php
@@ -506,7 +506,9 @@ if (!mkgetdir(dirname($page['derivative_path'])))
 }
 
 ignore_user_abort(true);
-@set_time_limit(0);
+if(function_exists("set_time_limit")){
+  @set_time_limit(0);
+}
 
 $image = new pwg_image($page['src_path']);
 $timing['load'] = time_step($step);