Someone tried to upload an avatar today generating a series of log errors.  Presumably there was a timeout uploading the file.  The missing index is what I'm reporting for now though.  Missing language string perhaps?  (English)
Type of error: Critical
URL /forum/index.php?action=profile;area=forumprofile;u=xxx
Type of error: Undefined
8: Undefined index: attach_timeout
URL forum/index.php?action=profile;area=forumprofile;u=xxx
File: /forum/sources/Errors.php
Line: 209