On Hook Dial Plan

We recently deployed an Asterisk System to our company (version and are using Polycom 430 and 650 phones. The issue we are having occurs when users are making outbound calls . If the phone is off the hook (no dial tone) our users need to dial 9-1-Area-Code-Number to make an outside call. If the phone is on hook (dial tone) the user only needs to dial 1-Area Code- Number. If they try to dial 9-1-etc while the phone is on hook they get a message stating that number is not a valid extension. We would like them to always dial 9-1-Area Code- Number,

Below is the dialplan line from our sip.cfg file

Our phones are running BootROM

Where do I make the change to allow on hook calls to dial 9 to get an outside line?

Thank you