[Serusers] Correcting SDP for Grandstream BT101

[Alex Mack]

Hi!

I'm using different kinds of hard-UAs, among them the Grandstream BT-101 
and Siemens optiPoint 400 standard SIP.
Grandstream sends the following rtpmaps out to the other party:

<snip>
a=rtpmap:0 PCMU/8000/3
a=rtpmap:8 PCMA/8000/3
a=rtpmap:4 G723/8000/3
a=rtpmap:18 G729/8000/3
a=rtpmap:2 G726-32/8000/3
a=rtpmap:15 G728/8000/3
a=rtpmap:99 iLBC/8000/3
a=fmtp:99 mode=20
a=rtpmap:9 G722/8000/3
</snip>

and the Siemens phone always states "user agent incompatible" - seems as 
if its complaing about the appended "/3" of every rtpmap. Regarding the 
RFC the third parameter states the count of channels (?).
With other UAs (XLite, Sipura) audio connection is possible.

Anyway is there a possibility to correct this problem using ser? Can I 
issue a command that removes every /3 from the rtpmaps coming from th 
Grandstream phone?

Alex Mack