FWSM probelm

Hi I have little problem with FWSM communication:

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fwm# sh failover
Failover On
Failover unit Secondary
Failover LAN Interface cos Vlan 41
Unit Poll frequency 500 milliseconds, holdtime 3 seconds
Interface Poll frequency 3 seconds
Interface Policy 50%
Monitored Interfaces 10 of 250 maximum
failover replication http
Config sync: active
Last Failover at: 22:55:07 Mar 13 2008

This host: Secondary - Standby
Active time: 1362 (sec)
ADMIN Interface inside (85.89.226.144): Normal
ADMIN Interface outside (0.0.0.0): Normal (Not-Monitored)

Other host: Primary - Active
Active time: 7045842 (sec)
ADMIN Interface inside (85.89.226.143): Normal
ADMIN Interface outside (0.0.0.0): Normal (Not-Monitored)


NP-PCcmplx logger frame timeout
ERROR: np_logger_query request for FP Stats failed TCP NPs 0 0 0 0
UDP NPs 0 0 0 0
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I can ping 85.89.226.143 but can't 85.89.226.144

I found in logs something like that:

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Jun 03 2008 10:09:02: %FWSM-1-105008: (Primary) Testing Interface inside
Jun 03 2008 10:09:02: %FWSM-1-105009: (Primary) Testing on interface inside Passed
Jun 03 2008 10:09:17: %FWSM-6-302016: Teardown UDP connection for faddr 158.98.141.165/11956 gaddr 85.89.226.143/161 laddr 85.89.226.143/161 duration 0:02:03 bytes 387
Jun 03 2008 10:09:20: %FWSM-1-105005: (Primary) Lost Failover communications with mate on interface inside
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I restarted standby firewall module, after that I can ping all IPs, everything look good, after few hours, I lost communication again.

Both firewalls have the same software:

[code:1]FWSM Firewall Version 2.3(5) <system>
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