It's not a problem for me but I just came across this strange
behaviour of Firebird 1.5.2

Firebird notices wrong column-positions like this

SELECT col1, col2, col3 FROM ... ORDER BY 0
or
SELECT col1, col2, col3 FROM ... ORDER BY 4

But it also accepts commands like this

SELECT col1, col2, col3 FROM ... ORDER BY -1
SELECT col1, col2, col3 FROM ... ORDER BY 1+1
SELECT col1, col2, col3 FROM ... ORDER BY 3-1
...

but doesn't give the "expected" results or errors.

Server Version: LI-V1.5.2.4731 Firebird 1.5
Server Implementation: Firebird/linux Intel

--Heiko