Need Change material field (MATNR) in FB02... can you help

Hi ALL...

I need to change material field in posted line items. Is their any way to open this field in FB02 i tries doing it with table V_TBAER ie setting in OB32 , but it still doesnt allow me field edition ...

Can this be done thru BDC or any function module is there?

Business requires it urgently.

Thnx in advance

Shubhada