"Cast" function for Access via TADOQuery


I'm trying to port a BDE app to ADO using Access 2002 as the database,
with Delphi 6.  With the BDE TQuery, I could use a cast SQL function

    SQLText := 'Select '
             + 'ItemNo, '
             + 'cast(ItemDesc as char(40)) as CastItemDesc '
             + 'from Table1.db ';

With ADO, the equivalent TADOQuery logic would use varchar instead of
char to get a variable-length field:

    SQLText := 'Select '
             + 'ItemNo, '
             + 'cast(ItemDesc as varchar(40)) as CastItemDesc '
             + 'from Table1 ';

The problem is that I can't seem to get any variation of the cast()
function to work (varchar or char).  It is a defined function in
SQL-92.  Would anyone know whether it is implemented with TADOQuery or
how I might accomplish this in ADO?

Thanks much for your thoughts!
Jim Williams