The SQL that mod_auth_mysql (2.20) generates does not
properly quote the column names. For instance, if you
you name the groups column, 'group', it uses the
following SQL for group auth:
select count(*) from groups where
username='someusername' and (group='somepassword')
Which fails because 'group' is a reserved word. You
should be able to fix this by quoting the column names,
like:
select count(*) from groups where
'username'='someusername' and ('group'='somepassword')