Dedicated server issue on mac in 1.5

I just upgraded from Torque v1.4 to v1.5

I am finding that in 1.5, when I run a dedicated server on the mac, clients that connect to it load the game very, very slowly.

I was running dedicated servers on the mac fine with 1.4. I am running dedicated servers on windows without a problem with 1.5

I can host a multiplayer game from an ordinary (non-dedicated) server on the mac, and clients that connect to it without a problem.

So, there is some issue specifically related to dedicated servers on mac with v1.5

Has anyone experienced this? Or can anyone suggest what to look at?

Thanks.