Sure - many ways.
The best/easiest is to look at the access log (e.g. /var/logs/apache2/access_log) and see what the last request was, and if it had anything to do with the "hang".
The Apache error log (e.g. "error_log") should be in the same directory. Look there, too.
Other tools might include:
* lsof: see what files/ports the process is using
* tcpdump or wireshark: take a network trace when the "hang" occurs.
Who knows - maybe you'll discover that the CLIENT might be at fault
* gdb: you can attach to the live, "hung" process and get a stack traceback (of exactly where it's hanging)
'Hope that helps .. and Good Luck!
Please post back what you find!