Problem in BDC for posting an amount feild, please help

I am doing one batch upload problem. Where I have to upload data from transparent table to amount field into Tcode FPE1. My problem is that when I tried to post this field I get the message 'Field is two big for screen field'. I debugged and found out that when I post amount field (type CURR Length 13 Decimal 2) into Internal table for type BDCDATA, the field get left aligned in Fval-bdcdata field which is of 132 character long. I also tried to change the type of amount field into Char type, but then I get the error 'Enter numeric value'. If you got any idea how to post this amount filed please to pass me.

Thanks and Regards,

Shekhar