Using FB 1.02 and IBO 4.2.Ib, I get the next error when trying order by
'PRONT' column. This happen if I'm not using a column name prefixed by
tablename in Ordering Items.

Error:
'Dynamic SQL Error
SQL Error code = -204
Ambiguous field name between table RELFAT and table CLIENTES
PRONT''

Query:
'select A.*
from relfat A
join clientes E on E.pront=A.pront'

Ordering Items:
NRF=NRF;NRF DESC;
Nome=NOME;
Pront=PRONT;
Data=Data;

KeyRelation=RELFAT

Now, If I use Ordering Items as:

Ordering Items:
NRF=RELFAT.NRF;RELFAT.NRF DESC;
Nome=RELFAT.NOME;
Pront=RELFAT.PRONT;
Data=RELFAT.Data;

All works well in case above. I remember I haven't this problem using
Interbase 6.0X. I am not selecting any columns from table Clientes. It's
used only to make a join.

I think I found a bug. Does someone has some comments about this case?

Luiz.