I'm not sure if this is a bug or intentional. I bought a Wraith tonight and equipped it with a fighting laser and a mining beam in the 2 small hardpoints.

This seemed to disable the auto-aim feature. The yellow reticle just stayed fixed straight ahead. (I also got 'no resource to mine' every time I fired but that was just a ui issue.)

Once I took out the mining beam and added a second laser, the auto-aim was back.

If a non-weapon is in the primary fire group/slot, auto-aim is disabled. This is a known bug-ish thihngy and has to do with the fact that auto-aim is calculated based on the primary fire group.