Debugging issues with bb-histlog.sh on 4.3.0

[Alan Sparks <asparks (at) doublesparks.net>]

I've some "random" failures on bb-histlog.sh, viewing items in the bb2
event log.  Some work as expected, but some when clicked appear to do
nothing.  Hitting the URL for that (say
http://den2sch17/hobbit-cgi/bb-histlog.sh?HOST=den1ws063&SERVICE=nfs&TIMEBUF=Mon_Jun_22_18:46:39_2009)
with curl shows a zero-length reply.  Checking the Apache error log
shows "Premature end of script headers: bb-histlog.sh, referer:
http://den2sch17/hobbit/bb2.html";.  I have found no core files left behind.

How is the best way to debug this problem, with no core files?  Is there
a good method to run this (or I suppose more specifically,
hobbitsvc.cgi) under the debugger and feed it the request so I can tell
why it is silently failing?

Thanks in advance for any suggestions.
-Alan