Asterisk crashes after call pick up - segment fault

Ok, guys, I have a bizarre issue.

I’m running Asterisk 1.6.2-beta (yes, I’m aware it’s beta) on Scientific Linux 5.2 (2.6.18-128.1.1). The server comes up, the SIP users connect fine… Dialing works. As soon as the dialed party picks up, Asterisk crashes with the Segmentation Fault. The call is established, but voice works only in one direction from the dialed party to the one dialing.

Any input is appreciated.