STO error!!!

Hi friends,

When i created STO(inter-company) with item category U, the sytems throws the message - <b>"Material not subject to inventory managment in plant"</b> but shipping Tab is coming.....

I customized:

Material master - suppling plant(views - basic data,sales data, MRP, Accounting data) for receving plant (views - basic data, Purchasing, MRP, Accounting)

>Customer Master created with respect to suppling plant and assigned it to Receiving plant....

>Vendor master created for receiving plant and assigned supplin plant to purorg data......

>Schedle line categories is assigned in sales and distribution....

>Shipping point is maintained for suppling plant....

>Delivery type is mainained NL & combination of order type UB & checking rule RP......

Could u help me to resolve this problem

With regards,,

Sathish....