Remove b=... from sdp

Hello,

I would like to remove two lines from SDP body:

INVITE sip:5551212@192.168.1.61:5060 SIP/2.0

Via: SIP/2.0/UDP 192.168.1.60:5060;branch=z9hG4bK4odk1f20a8g0gdcln7c0

From: sipp <sip:+2125551212@192.168.1.60:5060>;tag=9hqq601-15329

To: sut <sip:5551212@192.168.1.61>

Call-ID: 9hqq601-45ad705ceba52d6aed059f6fb0ad3bbb-06a3gu0

CSeq: 1 INVITE

Contact: sip:sipp@192.168.1.60:5060

Max-Forwards: 70

Content-Type: application/sdp

Content-Length: 174

v=0

o=user1 53655765 2353687637 IN IP4 192.168.1.60

s=-

c=IN IP4 192.168.1.60

b=RR:0

b=RS:0

t=5 2

m=audio 10000 RTP/AVP 0 22

a=rtpmap:0 PCMU/8000

a=rtpmap:22 G728/80

Any idea how to do it?

thx

Tonci