AASTRA 4425 IP Vision (SIP) for MX-ONE User Guide - Manual (Page 81)

Other Useful Features
Dialog 4425 IP Vision 82
Other Useful Features
Account Code
This feature is used to charge a call to an account number or to
prevent unauthorized calls from your phone. The Account Code
can have 1 to 15 digits. *61* z #
Dial, enter the Account Code and press.
Dial tone.
Note: Finland and Norway, dial
* 7 1 *
Code
#
.
Call Press.
z
Dial the digit or digits to get an external line, external number
and press.