I tried Firebird 1.0 and 1.5 on my win2k PC. Everything works fine
except one major problem: it seems I can not run any built-in SQL
function such as rtrim(), strlen(), etc. Actually I can run none of
the SQL function mentioned in the manual. Every time I get the error
such as the following:

Dynamic SQL Error
-SQL error code = -804
-Function unknown
-RTRIM

Is there anything I missed? Thanks for your pointer.