[Serusers] SER 0.9.6 and MySQL connection failed

[Mitya]

Hi all,

I'm running SER 0.9.6 on a Debian Etch, compiled it from source, using 
etch's libmysqlclient5 to connect a mysql server 5.0.20 (running on a 
different server, but on the same LAN)

>From my ser.cfg:

modparam("usrloc", "db_mode",   1)
modparam("usrloc", "timer_interval", 10)
modparam("usrloc", "use_domain", 1)
modparam("usrloc", "db_url", "mysql://ser:xxxxx@x.x.x.x:3306/ser")


When I start SER, everything seems to be fine for a while.
After about one day, when I unplug my UAC and the registration expires, 
SER can not remove it from the database because it says:

Oct 18 14:47:07 sip ser[21813]: Binding 
'1111111 at 1.2.3.4','sip:1111111 at 2.3.4.5:1164' has expired
Oct 18 14:47:07 sip ser[21813]: submit_query(): mysql_ping failed
Oct 18 14:47:07 sip ser[21813]: submit_query(): MySQL server has gone away
Oct 18 14:47:07 sip ser[21813]: db_delete: Error while submitting query
Oct 18 14:47:07 sip ser[21813]: db_del_ucontact(): Error while deleting 
from database
Oct 18 14:47:07 sip ser[21813]: wt_timer(): Error while deleting contact 
from database


If I restart SER, everything works fine (for a while) again.

I'm sure that _NO_ONE_ was restarted the MySQL server during the test 
period.
I can reproduce it at any time.

Is it a known issue, or do I have a special case ?

Every comments are welcome.

Thanks,
Mitya