diff --git a/xhprof_lib/utils/xhprof_lib.php b/xhprof_lib/utils/xhprof_lib.php
index c63bf1eb..507e6694 100644
--- a/xhprof_lib/utils/xhprof_lib.php
+++ b/xhprof_lib/utils/xhprof_lib.php
@@ -19,8 +19,10 @@
 // Do not add any display specific code here.
 //
 
-function xhprof_error($message) {
-  error_log($message);
+if (!function_exists('xhprof_error')) {
+  function xhprof_error($message) {
+    error_log($message);
+  }
 }
 
 /*