Heh, was just testing out the latest version of the mission pack, and forgot I'd upped the likelihood that the AI might try for a capture when there are three of them working together - make sure you keep your marines stocked, and keep an eye on your marine count and your allies!
If they cap one of your allies they'll attempt to disengage it while they continue to fight you.
One of the unexpected side effects is that it sometimes leaves the AI more vulnerable to capture, since they've got a reduced marine count - even transporter-challenged races have a shot at captures, if they live long enough.
IIRC capture attempts are most likely when facing three enemies in their space (ED5Fleet Action and ED10PatrolEnemy), but your AI allies are likely to help you in capture attempts in your own space (ED5PlayerFleet and ED10Patrol)
just a friendly heads-up for the next time a server runs with the updated pack
dave