AASTRA 4422 IP Office for MD Evolution User Guide - Manual (Page 89)

89 MD Evolution – Dialog 4422 IP Office
Group Services
The GSM mobile telephone may also be directly called through the
number associated with the internal dummy extension. This may be
used in conjunction with a personal group. However, the GSM
mobile telephone will still retain its regular number.
Note: The Mobile Extension service is also totally applicable
to your residential extension connected to the pubic ISDN
network. Whenever necessary, contact your system admin-
istrator for more information concerning the availability of
this specific service for your telephone facility.