VLAN voice command unavailable on Procurve 4108GL switches

[PLS Cayman]

I have a number of 4108GL switches that I am trying to configure to support Mitel IP phones. On other switches such as the 2650 I had to upgrade the firmware before the “voice” command would be recognised, but on the 4108GL running G.07.109 the voice command is still not available.

Without configuring the vlan for voice, I have to manually configure each phone. I am trying to determine what it is the “voice” command actually does, and is there is any way of emulating its functionality on the 4108?

Without the ability to issue the voice command, any Mitel handsets connected to the switch do not find the right vlan. They can each be manually configured for the voice vlan, but there are a large number of them and it would be nice not to have to take this extra step.

Any help appreciated! Thanks.