You can add exceptions this way:
In the Security and Patch Manager, select the third icon drop-down and select "LANDesk Antivirus Settings" and then select the Real-Time Protection tab, and then you can add files, folders, or extensions to the list of exclusions.
You will want to do this also for the Virus Scan tab.
Thanks a lot. This is exactly what I needed. One more question though. How do I push an update to a client after changing this without reinstalling it?
If you have made this change to your current AV settings then there is nothing you need to do. The client should receive these new settings the next time it runs a vulscan. If you created a new AV setting, then you can schedule an settings task from within the Security and Patch Manager, under Create a Task->Change Settings.