Ast 1.2.10 send DTMF RFC2833 UDP BAD CHECKSUM

Using: Asterisk 1.2.10
OS: Linux ast2 2.6.9-39.0.2.ELsmp #1 SMP Thu Jul 13 06:56:04 CDT 2006 i686 i686 i386 GNU/Linux

I’m having trouble with the dtmf=rfc2833 that asterisk sends, it’s never accepted by my equipment at the other end (Tekelec T7000)
And I did some tcpdump, and after checking it in ethereal, it seems that the UDP packets that Asterisk sends for DTMF all have bad CHECKSUM
Checksum: 0x85ba [incorrect, should be 0x2390]
And in fact, all those packets are sent with checksum= 0x85ba

I cheked the release notes, and didn’t see anything about that in the newer version, but is it problem that is fixed in newer versions?

Oh, also the Asterisk sets ‘Event Duration: 0’ in the first 3 rtp dtmf packets sent, I don’t think that follows the standard.

Nobody got any idea of why the bad UDP checksum?

I’m having a similar problem with outbound DTMF to my carrier over a SIP trunk. The carrier reports seeing the duration of 0, and I’m only getting about 50% of DTMF tones to go through.

Using Asterisk 1.2.14