SQL语句的问题！为什么执行后提示错误！

SELECT getOrgRefNo([RefNo]) AS FC_RefNo, FinalConfirm.PONO, FinalConfirm.Rev, FinalConfirm.B_QTY, FinalConfirm.DelDate, FinalConfirm.FOBDate
FROM FConf_Detail INNER JOIN FinalConfirm ON (FConf_Detail.PONO = FinalConfirm.PONO) AND (FConf_Detail.Rev = FinalConfirm.Rev)
WHERE (((getOrgRefNo([RefNo]))<>getOrgRefNo([forms]![F_FConf]![cboRefNo])));

getOrgRefNo是一个方法：
Function getOrgRefNo(str As String) As String
Dim i As Integer
i = InStr(1, str, "-")
If i > 0 Then
    getOrgRefNo = Left(str, i - 1)
Else
    getOrgRefNo = str
End If
End Function

但是执行后总是提示错误：
特定字段'[RefNo]'可以参考SQL语句From字句列表中的多个表!

请教如何解决这个问题！！！