AASTRA 4222 Office for MX-ONE (TSE) User Guide EN - Manual (Page 63)

63 Dialog 4220 Lite/Dialog 4222 Office
Other Useful Features
Additional Directory Number
You can be assigned (preprogrammed by your system administrator)
one or more Additional Directory Numbers (lines) on free function
keys.
To answer, make calls and use features on the additional directory lines,
use the same procedure as for the Triple Access Lines, unless you have
other instructions. However, you have to press the additional Line key
after lifting the handset.
Example:
To make a call on an additional directory line:
u
Lift the handset.
Additional line
Ô
Press.
Note: Function key preprogrammed by your system
administrator.
z
Dial the extension number.