Weird problem involving a TCP server, a hung connection, and QTONVLIC

I just found a problem on a customer box, and while I was able to get them back up and running, I can't make head or tail of what happened in the first place.

It seems that the server for our "Wintouch" CRM application would not start. I tried starting it myself, and found that it was crashing on takeoff, in a way that suggested there was a hung connection on its port.

Sure enough, that's exactly what I found: a connection that had been hung for days. When I tried to kill the connection from WRKTCPSTS, several things happened:

First, I got a message that it was unable to end the connection.

Then, the connection ended.

Then, I found a bunch of spool files that weren't there before I killed the connection.

Looking through the spool files, I found that several were joblogs from my current terminal session (!?!), and a couple were references to a problem log entry.

So I did a WRKPRB, and got something referring to QTONVLIC, which I'd never heard of, and I couldn't find much in a Google search, that would indicate what it is or what it does ("LIC" in the name, of course, suggests licensed internal code).

I'm told that the customer removed a piece of network hardware (external to the AS/400) over the weekend.

Can anybody shed any light on this?

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JHHL