I tried Martin's first patch with a newly-cvsup source and have not been able to cause another crash after more than 20 reboots, and rebooting into the bsd.rd.
I do still have the panicd vm console. Is showing one of the isc bind named threads with thrsleep tell you anything? ddb{3}> ps PID PPID PGRP UID S FLAGS WAIT COMMAND 93716 1 93716 0 3 0x100083 ttyin getty 29744 1 29744 0 3 0x100083 ttyin getty 97017 1 97017 0 3 0x100083 ttyin getty 15604 1 15604 0 3 0x100083 ttyin getty 82395 1 82395 0 3 0x100083 ttyin ksh 16881 1 16881 0 3 0x100098 poll cron 82696 1 82696 741 3 0x98 sigwait named *82696 1 82696 741 7 0x4000010 named 82696 1 82696 741 7 0x4000010 named 82696 1 82696 741 7 0x4000010 named 82696 1 82696 741 7 0x4000010 named 82696 1 82696 741 3 0x4000090 thrsleep named 82696 1 82696 741 2 0x4000010 named 54311 1 54311 99 3 0x100090 poll sndiod 4358 1 4358 110 3 0x100090 poll sndiod 7746 64349 64349 95 3 0x100092 kqread smtpd