VNC and winNT locked screens.

[VNC user]

I have noticed that I am unable to connect to a vnc server running on
winNT if my screen is locked.  My workplace requires me to set my system
to lock its screen after a few minutes of inactivity.  This basically
means that VNC is useless for this purpose (logging in remotely to my work
machine) because my desktop is locked when i am not around.

Is there a way around this problem... is it possible to unlock the desktop
from a vncviewer?  

Any help would be appreciated.

-jeff