Plantronics 72442-01 HIS Cable pinout

[metajemo]

hello,
I would like to use my standard headset on an avaya 1608 phone and I'm trying to find out if that is possible. The headset for avaya is quite expensive and usually It needs a Plantronics 72442-01 HIS Cable as well. Does Anybody know the pinout from the avaya, the cable scheme, the resistance of the cable and of the headpiece? I've been trying to find out some more information but up to know I found nothing.....
Any help on that is appreciated
Thank you