RT2 just stops working?

We recently added a few queues to our RT2 install and suddenly correspondence
is not getting delivered… I looked for an error and didn’t find one in
maillog or messages… I tried nuking rt2/local/templates, just incase that
was a problem and still RT2 thinks it sent correspondence but none is sent.
Is there a good spot to search for error logs or a method I can apply to
tracking the problem? Anyone have experience with this sort of delivery

Thanks in advance…