Tax not being charged in offline mode

When the POS software jumps into offline mode it doesn't charge tax to any items being rung up. It won't even allow you to check the taxed box. Once the register goes back into normal mode connecting back to the  database it start charging taxes again. It basically won't charge tax in offline mode. The RMS version is 2.0.0166 with Feature Pack1. 

Thanks for your help

Dave