PP5.31 : sql errors with separate IPB user database

[flat]

Hello,
Since I upgraded to PP5.31, I get "MySQL Error Report" emails notifications and sometimes PHP warnings appear on my gallery, such as :

Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /galeries/forums/ib2.php on line 94

I think this is due to a bad database selection when updating user's count cache. I'm using a database "teddy2you2" for photopost, and another database "teddy2you3" for Invision Board 2.

Here are errors I received by email :

An error was encountered during execution of the query:
SELECT * FROM ipb_members
The query returned with an errorcode of:
Table 'teddy2you2.ipb_members' doesn't exist

An error was encountered during execution of the query:
SELECT
ipb_members.id,ipb_members.name,ipb_members.email, ipb_members.member_login_key,ipb_members.mgroup,ipb_members.time_offset, ipb_sessions.id,ipb_members.skin,ipb_members_converge.converge_pass_hash, ipb_members_converge.converge_pass_salt
FROM ipb_members
LEFT JOIN ipb_sessions ON ipb_sessions.member_id=11877
LEFT JOIN ipb_members_converge ON
ipb_members_converge.converge_id=ipb_members.id
WHERE ipb_members.id=11877
The query returned with an errorcode of:
Table 'teddy2you2.ipb_members' doesn't exist

An error was encountered during execution of the query:

SELECT
ipb_members.id,ipb_members.name,ipb_members.email, ipb_members.member_login_key,ipb_members.mgroup,ipb_members.time_offset, ipb_members.skin,ipb_members_converge.converge_pass_hash, ipb_members_converge.converge_pass_salt
FROM ipb_members
LEFT JOIN ipb_members_converge ON
ipb_members_converge.converge_id=ipb_members.id
WHERE name='sébastien'
The query returned with an errorcode of:
Table 'teddy2you2.ipb_members' doesn't exist

Thanks in advance