Bypass Time Restrictions by Logging Into Alternative Machines

I just figured out that my kids found a simple workaround to time restrictions.  They where capped at 1 hour each per school day.  There are 3 kids with 4 machines (1 Mac OS X 10.6.3, 1 Vista 32, 2 Vista 64) in the house, all of which are installed with latest version of Norton & Parental Controls.  Further, all machines have individual logins for each child, each of which is a restricted account.

 

It's my understanding that time is supposed to be tracked at child account across any computer with the Norton Parental controls installed and associated to correct online account.  Well, my guys realized that if they run out of time, they log out and go onto another machine to get a fresh hour.  I've not tested fully yet, but they admitted the "workaround" works.

 

As time is limited, I thought I would post seeking feedback if this is a known issue...  Meanwhile, they have no computers until I find a fix or another product to solve this dilemma...

 

Thanks