Segmentation fault problems

[Ali Nebi]

Hi all, 

i hope that here i will find solution for my problem.

We get these messages in a mail server:

in kernel.log 

Sep 12 11:28:44 hermod kernel: lmtpd[3555]: segfault at 0000555554000000
rip 00002aaaacb11af9 rsp 00007fffd7127c50 error 4
Sep 12 11:49:35 hermod kernel: pop3d[9756]: segfault at 00000000fffffff7
rip 00002aaaacb11adb rsp 00007fff8268bbb0 error 4
Sep 12 12:04:43 hermod kernel: pop3d[10667]: segfault at
00000000fffffff7 rip 00002aaaacb11adb rsp 00007fff4738cab0 error 4

and 

these in maillog

Sep 12 12:24:31 hermod postfix/lmtp[12112]: warning: to prevent loss of
mail, turn off command pipelining for /var/lib/imap/socket/lmtp with the
lmtp_discard_lhlo_keyword_address_maps parameter
Sep 12 12:24:31 hermod postfix/lmtp[12108]: warning: to prevent loss of
mail, turn off command pipelining for /var/lib/imap/socket/lmtp with the
lmtp_discard_lhlo_keyword_address_maps parameter
Sep 12 12:24:31 hermod postfix/lmtp[12112]: warning: non-LMTP response
from hermod.iguanait.com[/var/lib/imap/socket/lmtp]:
2aaaab391000-2aaaab392000 rw-p 2aaaab391000 00:00 0 
Sep 12 12:24:31 hermod postfix/lmtp[12108]: warning: non-LMTP response
from hermod.iguanait.com[/var/lib/imap/socket/lmtp]:
2aaaaaad2000-2aaaaaad3000 rw-p 2aaaaaad2000 00:00 0 

How can i understand what is the real problem and how to solve this?

We have installed on fedora 6 - cyrus-imapd-2.3.9-6.fc6, postfix-2.3.3-2

These are the lines for transport in /etc/postfix/main.cf:
default_transport = smtp
mailbox_transport = lmtp:unix:/var/lib/imap/socket/lmtp 

Thanks in advanced!