[Freeswitch-users] custom avp in radius

Hi, Does anyone know of a way to add custom information in AVP in radius accounting messages? I can see in the radius dictionary there are many AVPs defined, but I'd like to add some additional custom text information. "Freeswitch-AVPair" seems like a generic AVP, but I cannot figure out how to use it (if it's intended for something like that at all). Maybe there is a way to set some variable in the dial plan and to use its contents to populate a general purpose AVP? If there is no such functionality what will be the best way to do it? I found similar feature added in the past (http://fisheye.freeswitch.org/changelog/FreeSWITCH/?cs=7529) and it doesn't seem too complicated. BR