Free goods with material type = ROH

Hello,

i would like to give free-goods for a particular finished goods sales.

the free-goods' material type is equal to ROH.

when i maintain the free goods from VBN1, system tells me that "xxx Material is not defined for sales org xxxx with dist. channel xxx".

the pb is for material type ROH, i can't select sales view,

is there any work around except

1. changing material type

2. customizing and add view for ROH

Thanks