Call to undefined function sq_send_mail()

Due to a recent spam incident (Nigerian boy guessed luser boy's pass I
installed the lockout plugin and configured it to send mail. I use the
compatability plugin 2.0.9.

Yet I get:
Fatal error: Call to undefined function sq_send_mail() in
/var/www-lighty/squirrelmail-1.4.15/plugins/lockout/functions.php on
line 1204

Accoring to google I should "update my compatability plugin". But it's
already the latest version!

--

-- 
Ralf Hildebrandt (i.A. des IT-Zentrums)         Ralf.Hildebrandt <at> charite.de
Charite - Universitätsmedizin Berlin            Tel.  +49 (0)30-450 570-155
Gemeinsame Einrichtung von FU- und HU-Berlin    Fax.  +49 (0)30-450 570-962
IT-Zentrum Standort CBF                 send no mail to snickebo <at> charite.de

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