[sork] can't change password in "PASSWD"

[Winnie]

When I wanted to change password, then the page of "passwd" was shown as 
"Failure in changing password on Exampe SQL Server: Incorrect Password"
I tried to view the "horde.log", then I got the following error:

Sep 20 09:54:24 HORDE [debug] [passwd] SQL Query by 
Passwd_Driver_sql::_lookup(): SELECT password FROM [sometable] WHERE USERID 
= ? [on line
117 of "/var/www/html/horde/passwd/lib/Driver/sql.php"]

pls help me...

thx a lot..