named crashes on assertion in rbtdb.c on sparc64/SMP

[KOT MATPOCKuH]

I updated system to r223824 and got named patched to 9.6.-ESV-R4-P3,
but problem is still exists:
07-Jul-2011 13:24:22.765 general:
/usr/src/lib/bind/dns/../../../contrib/bind9/lib/dns/rbtdb.c:1622:
REQUIRE(prev > 0) failed
07-Jul-2011 13:24:22.781 general: exiting (due to assertion failure)

How can I find root cause of the problem?

-- 
MATPOCKuH