Change the Reconciliation Account for the FI Document

Hi,

I like to change the reconciliation account of the line item in a FI Document, which will be created FROM MIRO or MIR6 trxn. I have tried the BTE - 00001120, I can modify the required field, but at the time of posting it's again fetching the default reconciliation account.

Can any one plz suggest me the way to solve the problem? Please suggest.

Thanks,

Kuntal