I have a Mitel 250 running 6.2 software. I have a couple mailboxes that require 0 to go to a different extensions. I have programmed the mailbox 0 option in the mailbox to go to the extension I want in DB programming. While listening to the users greeting, I press 0 and nothing happens. Am I missing turning on a flag? If so, where is it? We have 8 SIP trunks and I know DTMF is working since they are answered by the AA full time and I can dial extensions and options through the CRA.