Milter-greylist

Hello,

I am using 3.1.4, but I got crashes earlier too. Decided to troubleshoot it.
How can I run milter-greylist from gdb? I tried gdb ./milter-greylist,
r -P /var/milter-greylist/milter-greylist.pid -p /var/milter-greylist/milter-greylist.sock -D,
but it stops after the first email (when it wants to print "(unknown id): addr
superafu.de[81.169.170.70] from <xxx@...> to <xxx@...> delayed
for 00:02:00 (ACL 103)" I assume). So I just ran
./milter-greylist -P /var/milter-greylist/milter-greylist.pid -p /var/milter-greylist/milter-greylist.sock -D
After about half a day it crashed:
*** glibc detected *** double free or corruption (!prev): 0x0a5441a8 ***
Aborted

How can I troubleshoot it?

Regards,
Nerijus