getting last oid in Visual Basic

Hi!

I have problem with getting the oid of last inserted row in Visual Basic.
If I update a recordset with a new row, and then I execute a query:
"select :LASTOID as loid"
then I get: ERROR:  parser: parse error at or near ":"

May be the driver connects to the server again, and cant't get the oid?

How can I get it with ODBC?

Thanks
Zoltan