I've noticed two issues on my site using the nodequeue beta..
(1) Sometimes I get this error (1-2 times daily)

Fatal error: Call to undefined function nodequeue_load() in /srv/www/dev.powerpoetry.org/public_html/includes/menu.inc on line 579

and (2) the nodequeue link does not appear in the admin > structure menu sometimes for 2-3 minutes.

During the duration of the error in (1), 30 seconds or so, the only pages that fail to load w/this error are ones that load a nodequeue.

These two issues make me think that the nodequeue module is getting disabled somehow briefly. It's possible that someone else is modifying or adding to a nodequeue, but they would not be turning on or off any modules. Could a module turn itself off briefly? Or, is there another way anyone can recommend to debug this issue? Thanks in advance!