[TYPO3-english] Error message class.t3lib_db.php line 704

[J. Schaller]

Hello all,

when logged in the backend of Typo3 4.4.4, I'm getting a couple of
these errors:

Core: Error handler (FE): PHP Warning: mysql_real_escape_string()
expects parameter 2 to be resource, boolean given in
/typo3_src-4.4.4/t3lib/class.t3lib_db.php line 704

Does anyone know what this might be and what should I do to
troubleshoot it? Thanks for any help (I'm not a programmer)!