I had this problem as well, and I had difficulty getting it resolved through the support group. I just "fixed" it yesterday and I thought I'd post the steps we took, just in case anyone is reading through these forums looking for possible hints or solutions (as I certainly was a few days ago!)
After upgrading to EV 6.0 and CA 6.0, we noticed that we were seeing this same 3310 error. We're using win2k server SP4, archiving from exchange2k SP3. It seemed no matter what we tried, we were unable to get the Journal Task to properly archive anything from our journaling mailbox. the Archiving Tasks all worked fine- no problems there. As the Journal Task is what feeds our email compliance system, this was a bit of a problem, to say the least.
We would see messages pile up in the journaling service j2 MSMQ queue, until it hit 1000 (the default service limit). at that point, it would continually error out, and only process one or two messages from the queue before it would error again. Many different attempts were made to clear this up, including removing/re-adding MSMQ, fiddling around with service account permissions, and other things- none of which seemed to work.
Backed up everything, and upgraded to EV6 SP2. problem still was there. In a fit of desperation, I moved the journaling mailbox to a different mailserver (14.5GB mailbox transfer takes a little while!) To make it start journaling from this mailbox, I had to go into the vault control panel, add the new server as an archiving target, add the new journaling mailbox to it, and delete the old one. I also created a new Journal Task for the KVS server prior to this (which won't populate with a target until you do the above steps) so I'm not sure if creating a new archiving target/journaling mailbox will do that step for you or not.
Anyway, this is the point at which I start to feel rather stupid, as I see it immediately start chewing through thousands of emails, doing it's job quite properly. The solution (for me) seemed to be the re-creation of the Journal Task, I think- the old one in MSMQ was called "journaling service" whereas the new one is called "Journaling Task", more in line with the new names for things. not sure if it's a remnant from upgrades, or just coincidence, but if you're having this problem it might be worth a few minutes of your time to try recreating the Journaling Task. I don't think the mailbox move is necessary, although it was convenient for me to do so, so I did it anyway.
My 2 cents on solving this problem. hopefully it is helpful for someone.
