I own a franchised Motel where sometimes I need to forward customer questions to our 1-800 number. I have a traditional landline phone set-up. My business does have multiple extensions with a Mitel SX-50 PBX. I would like to set-up a phone with call forwarding on one of my extensions - but the phones out there say they are "SIP" and are IP phones - so I don't know if they'll work with my phone system.

Any insight to see if it'll work? Are there any other options that fit my criteria?