Log's for app vanishing

I've got a deployed app (one instance) with an output path set.  (Same
directory as all my other apps, which are logging fine)  I had a situation
last week where the logs for this app were not showing up, so upon
restarting it a few times, it corrected.  We've been experiencing some
seemingly random exceptions the last day, so this morning I went to check
the log file and it's now missing again.  The path I have set in Monitor is
/tmp/ which is the same for everything else.  What could be going on?  I
really need to debug this exception but am a bit hamstrung due to this
logging problem.  Thanks for any suggestions, as always;-)
-- 
William Hatch
Eng. Visual Media Collection
Cornell Lab of Ornithology
Macaulay Library
Voice (607) 254-2116
Fax (607) 254-2439