>Sergey,
>If I run those statements:
>

>csql = "select * from prestacoes where data_venc >= '2005/09/23'"
>csql = "select * from prestacoes where data_venc <= '2006/02/28'"
>

>It returns this message:
>"The conversion of char data type to smalldetime data type resulted in an out-of-range smalldatetime value"
>

It should wor the way it's. You can use SPT parameters as Cetin suggested or try

csql = "select * from prestacoes where data_venc >= '2005-09-23'"
csql = "select * from prestacoes where data_venc <= '2006-02-28'"