Cellular Extension - Is defined as a specific example of the Extension Anywhere™ capability of an AltiGen telephone system, any Cellular, Wireless or PCS telephone with a unique number can call into an AltiGen telephone system and be activated as a fully functioning extension of the business telephone system; The Cellular Extension capability extends PBX phone system extension capabilities to any mobile telephone or remote telephone; With the Extension Anywhere capability a Cellular Extension can be activated by any cell phone, PCS phone that has a Direct Inward Dialing number and can become a remote AltiGen telephone system extension and have the same call routing, call handling, call transfer, conferencing and company voice mail, voice messaging, and call center agent functions as any internal extension; These features will be delivered to the external mobile telephone from the AltiGen telephone system