It looks like your jboss server runs out of threads for allocation and waits for a new one to become available. Try running a thread dump (ctrl- \) and see if any threads are detected suspiciously blocked and waiting in some of your codes. Perhaps you are at a dead end or have a memory leak that causes old threads to lock and never be released.
Alternatively, try to do what your boyfriend did, i.e. increasing the number of available threads.
edit: For simpler tips, this post may come in handy.