Aastra Telecom SIP 57I - Manual (Page 360)

Operational Features
5-150 41-001160-00, Release 2.1, Rev 04
IP Phone Administrator Guide
Operational IP Phone Features
Using a BLA Line on the IP Phone
If you have either a global or per-line BLA configuration, and you want to share a
call on the line with a BLA group, you need to press the Hold button before
sharing the call with the group.
For example, if line 1 is configured for BLA, and you pick up a call on line 1, you
must press the Hold button to share the call with the BLA group.
If you pick up a call on line 1 configured for BLA, and another call comes in on
line 2, you can pick up line 2 without putting line 1 on hold. The line 1 call will
be on hold automatically; however it is on hold locally only. The line 1 call
cannot be shared with the BLA group.
Note: The Hold button must be pressed for a call on a BLA line to be
shared with the BLA group.