I am running CUCM 4.2(3)sr4b, latest software for 7962 SCCP phone and 7915 expansion modules. When I go to configure the phone button template, it only gives me the option to configure 34 lines, 6 on the base phone and 28 on the expansion module. According to the 7915 expasion module data sheet, with my CUCM version, I should be able to have support for up to 42 buttons. Any insight as to how I can get to 42? THANKS!