"Your request produced an error."

I have an app I am hosting for someone.   I do not have the source.  He does not have the source either (it was written for him by some consultants long ago).

It had been running fine last I heard but yesterday the guy for whom the app is running came to me and said that you got an error when you tried to actually do anything.   It has a direct action to login with and when you do that the browser says

"Your request produced an error."

The output log has one line:  [2013-9-11 23:43:59 MDT] <WorkerThread2> An exception occurred while trying to open a channel: N/A

I checked the connection dictionary and it is correct (I can use the info to log in using sql92 for example)

I cannot find any exceptions or anything.  I tried running the app by hand at the command line and when I connect to it through the browser I get nothing but that line in the output log.  No exceptions on screen or in the log.

The database is a FrontBase 5 on Linux.   Wo is running on FreeBSD with Java7

I am not sure what to do at this point.  It has been a while since I debugged this sort of issue.

Thanks
Chad