If you open a document from a webdav server, then leave it open for a long time (minutes? hours?) then attempt to save changes, OOO hangs for a long time then comes back with "general internet error". It doesn't help to go to file>open and browse to the location, force it to talk to the webdav server (didn't ask me to re-authenticate, clearly still knew how) -- attempting to save (ctrl+s) still doesn't work. Did not attempt save-as. However, after disconnecting from the vpn, putting the laptop into standby, and coming back the next day (in fact, did this while it was still trying to save and was confused), I got a different error, this time clearly indicating the connection had been dropped; after reconnecting to the VPN, I was able to ctrl+s and save my changes without any trouble.

It seems to me that OOO is attempting to keep a connection to the webdav server alive for the duration of document editing, but doesn't notice if the connection gets dropped (apache decided to kill it?), and doesn't know to always reconnect properly. If it, at some point, realizes that's the problem, it can recover from it. I'm guessing that the vpn connection drop made the tcp/ip connection drop obvious. That only works for me (outside the corporate network) not for my users (corporate cubicle farm.)

I've also seen this happening in LibreOffice 3.4, running on Server2008, but I haven't retested all OOO/LO versions on all OS's, so I'm providing the versions installed on my laptop. (But that's not the only version affected.)

Environment:
OOO -> Apache 2.0.x -> mod_jk -> Tomcat 6.x -> custom WebDAV server + JESPA (NTLMv2) -> AD
I haven't tuned keep-alive settings anywhere (don't feel I should have to); JESPA is set to 300 second session lifetime, I think.