Error Posting on Activity Stream

I'm getting this error when I try to post a comment on the Activity Stream:

[21-Dec-2012 06:14:50 UTC] PHP Fatal error: Call to undefined function wp_get_the_attachment_link() in wp-content/themes/bp-daily/library/functions/loop-functions.php on line 225
[21-Dec-2012 06:53:39 UTC] PHP Fatal error: Call to undefined function wp_get_the_attachment_link() in XXXXX-

This is a new error as of yesterday. I've been trying to fix some problems caused by the 3.5 update. I made a change to my config file but have restored to the original. (Although I'm not sure if error was there before I made the change.)

Thanks for any help.