Help with ODBC to Access query

Hello, I'm trying to get the following query to work:

    $query1 = 'SELECT COUNT(RunNumber) AS RunCount,
                      DatePart("m", CallDate) AS MonNum
                FROM CallData
                WHERE (CallDate Between #1/1/00# AND #12/31/00#)
                  AND Driver = 1731
                GROUP BY DatePart("m", CallDate)';

It returns the following error: Warning: SQL error: [Microsoft][ODBC Microsoft Access Driver] Too few parameters. Expected 1., SQL state 07001 in SQLExecDirect in d:\internet\apache\htdocs\db\test.php on line 48

Line 48 is :     $result = odbc_exec($connect, $query1);

The connection is established okay, as other queries work:

    $query2 = "SELECT RunNumber, CallDate AS TDate, CallUnit, CallDutyCrew AS Crew, PtNum, NatureFull, Driver, Attendant1, Attendant2
                FROM CallData
                WHERE (CallDate Between #1/1/00# AND #12/31/00#)
                  AND Attendant1 = $id
                ORDER BY RunNumber";

I've tried escaping the m's in the DatePart (I initially used double-quotes " " around the query string), tried changing the COUNT(RunNumber) to COUNT(*), etc without success. The query runs fine as written if entered directly into Access. Any ideas? SWS