What codecs does the 2.3-Gingerbread Internet calling (SIP) use? I am looking at the internet calling options in 2.3-Gingerbread. Does anyone know what codecs this dialer uses? 
Can the codecs be configured?
From a packet capture, the codecs are:


GSM-EFR 8Khz
AMR 8Khz
GSM 8Khz
G.711/PCMU 8Khz
G.711/PCMA 8Khz


Here's the tidbit from the RTP packet capture:

m=audio 22728 RTP/AVP 96 97 3 0 8 127
a=rtpmap:96 GSM-EFR/8000
a=rtpmap:97 AMR/8000
a=rtpmap:3 GSM/8000
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtpmap:127 telephone-event/8000
a=fmtp:127 0-15


I couldn't find a way to configure the codecs either.