Help debugging Trace/BPT trap on MacOSx 5.6.1

Hi All,

We are trying to run our app with latest ruby 1.9.1-p243 and rails
v2.3.4 but when we hit some of the controllers mongrel quits with
“Trace/BPT trap” error, same thing happens with webrick. There are no
additional logs! We have all the latest gems and plugins installed.

I would like to debug and see what causing this this but I wasn’t very
successful. Can you point me to some tools that I can use? I am toying
with Dtrace but haven’t figure it out yet.

thanks,
–Hakan