Too few parameters. Expected 2 ?

Dette Select statement kan fint køres i en Access query, men når jeg vil kalde den via ASP får jeg en fejl.

Fejlen:
[Microsoft][ODBC Microsoft Access Driver] Too few parameters. Expected 2.

Koden :
SQL = "SELECT DATEPART(""m"", LetterDate) AS Maaned, DATEPART(""yy"", LetterDate) AS Aar, COUNT(LetterID) AS Antal "
SQL = SQL & "FROM _tblLetter "
SQL = SQL & "WHERE (LetterReplied = 1) "
SQL = SQL & "GROUP BY DATEPART(""m"", LetterDate), DATEPART(""yy"", LetterDate) "
SQL = SQL & "ORDER BY DATEPART(""yy"", LetterDate), DATEPART(""m"", LetterDate)"

hvad er det lige der går galt ?