how to search smalldatetime field with a querystring value? ASP/SQL

["tradmusic.com" <sales@xxxxxxxxxxxxxxxxxxxx>]

I'm passing the following date, via a querystring, to a page that has a 
recordset containing a smalldatetime field:
page.asp?eventdatetime=2008-09-26

Problem is, the recordset is either producing no results, despite there 
being events in the table, on that date.  If I change the querystring to any 
of the following:
dd-mm-yyyy
dd/mm/yyyy
yyyy/mm/dd

I get an error about data type mismatch.

I know this is something silly...can anyone tell me what I'm doing wrong? 
Thank you.

Regards
Nath.