problem with unit of measure in BAPI for SO

hi friends,

i am owrking with BAPI for sales order BAPI_SALESORDER_CREATEFROMDAT1

problem is that

our base unit of measure is KG and i am passing MT(metric tone) for SO bapi in field sales unit directly by execuiting the bapi function module it was posting with out any problem.

same if i pass MT throught program it is giving an error as not maintained for item 00010

what will be the problem. should i pass any other field also?

thanks and regards,

venkat suman.