Torque user activity

Hey everyone,

Can someone clarify to me if / how torque handles console activity.   
We are in the midst of moving from PBS pro to torque for a "partial  
availability" cluster that we run (available between 2am and 7am) on  
some campus desktop machines.  We wanted to know what the best way to  
go about detecting whether or not a user is logged in at the console  
so as to prevent computers that are in use from starting jobs.

In my 20 mins or so of googling I could not find anything relating to  
this, so I figured here would be a good place to ask :).

Thanks,

Adam.