[horde] errors in mysql

[alan walters]

i have upgraded php to 4.3.9 and mysql to 4.0.20 and now i get this error 
any ideas???



Nov 01 10:36:00 HORDE [emergency] [horde] DB Error: extension not found: 
mysql, , /var/lib/mysql/mysql.sock, unix, localhost, horde, horde, horde, 
iso-8859-1, horde_sessionhandler [on line 199 of 
"/usr/share/pear/Horde/SessionHandler/sql.php"]

Nov 01 11:03:11 HORDE [emergency] [horde] DB Error: extension not found: 
mysql, , /var/lib/mysql/mysql.sock, unix, localhost, horde, horde, horde, 
iso-8859-1, horde_sessionhandler [on line 199 of 
"/usr/share/pear/Horde/SessionHandler/sql.php"]

Nov 01 11:03:38 HORDE [emergency] [horde] DB Error: extension not found: 
mysql, , /var/lib/mysql/mysql.sock, unix, localhost, horde, horde, horde, 
iso-8859-1, horde_sessionhandler [on line 199 of 
"/usr/share/pear/Horde/SessionHandler/sql.php"]

Nov 01 11:07:26 HORDE [emergency] [horde] DB Error: extension not found: 
mysql, , /var/lib/mysql/mysql.sock, unix, localhost, horde, horde, horde, 
iso-8859-1, horde_sessionhandler [on line 199 of 
"/usr/share/pear/Horde/SessionHandler/sql.php"]

Nov 01 11:07:34 HORDE [emergency] [horde] DB Error: extension not found: 
mysql, , /var/lib/mysql/mysql.sock, unix, localhost, horde, horde, horde, 
iso-8859-1, horde_sessionhandler [on line 199 of 
"/usr/share/pear/Horde/SessionHandler/sql.php"]

Nov 01 11:07:41 HORDE [emergency] [horde] DB Error: extension not found: 
mysql, , /var/lib/mysql/mysql.sock, unix, localhost, horde, horde, horde, 
iso-8859-1, horde_sessionhandler [on line 199 of 
"/usr/share/pear/Horde/SessionHandler/sql.php"]

Nov 01 11:12:04 HORDE [emergency] [horde] DB Error: extension not found: 
mysql, , /var/lib/mysql/mysql.sock, unix, localhost, horde, horde, horde, 
iso-8859-1, horde_sessionhandler [on line 199 of 
"/usr/share/pear/Horde/SessionHandler/sql.php"]