Alcatel Unleashed

hello guys,
OXE R 11.2 media gateway. im using GD3. i need to connect the system to a paging / public address system. its working fine when i configured the AFU directory number. i get the audio out from the Adio out put ping 4 and 5. now the issue is this.
the public address system need a on / off or a 12v contact from the oxe. this is to notify the PA system that some one is PA from the system and it will disconnect the mic of the PA.
i have gone through the OXE docs but couldn't get any on this issue. even the AFU directory number i got to find out from here as its not mentioned in the system docs. any way just wondering can i get the contact ot 12v out put from the Audio port in the GD3 when i call the AFU directory number? where cant i find the steps??

thanks in advance guys...

you could see if the amp has a VOX (voice operated switch) input or maybe see if you can get a seperate vox adaptor.
I assume you need this to switch off another source (like background music) when paging