Departments and COS

SUGGESTED

I hope I can explain this correctly.  I'm looking at setting up a Dept for a single business unit that we'd like to track separately from the overall business.  So far it looks like it will work very well.  The only thing that I can't seem to get to work is the inventory to COS entry that occurs when recording a sale.  Right now, the cost of sale is being recorded to the expense account (without department) even though the Sales account is chosen with a department.  Is there a way for the cost of sales to be recorded to the account with same department as the revenue, without having to set up a separate item in the system for the same item that might be sold through separate departments.  Hopefully someone can understand what I'm trying to ask!  Thank you.