tax calculation issue in bapi upload

Hi Friends,

I have developed one bapi upload program where in Iam using function module ' BAPI_ACC_DOCUMENT_POST '.

This should upload data into the transaction F-02. In this transaction, we have ' calculate tax ' check box in the second screen.

My requirement : I need to make this 'calculate tax' check box selected while uploading itself. For this I have prepared one excel flat file with calculate tax field (xmwst) and passed the value 'X' for all the records in the flat file.

But in bapi structures (import parameters), Iam unable to find the tax_calculation field for assigning the flat file field.

Can anybody give me an idea of how to approach.

Thanking you,

Regards,

Murali Krishna . T