diff --git a/src/sbbs3/js_global.c b/src/sbbs3/js_global.c
index 1db57360f2b7b3a6bd037f0ebd4bd305b64c8e60..82f6b3a124271dd1f6fd11529938e26db5d32d37 100644
--- a/src/sbbs3/js_global.c
+++ b/src/sbbs3/js_global.c
@@ -2467,7 +2467,7 @@ js_internal_charfunc(JSContext *cx, uintN argc, jsval *arglist, char *(*func)(ch
 		return(JS_TRUE);
 
 	js_str = JS_NewStringCopyZ(cx, func(str));
-	free(str);
+	free(str);	/* MSVC detected heap corruption here! */
 	if(js_str==NULL)
 		return(JS_FALSE);