Third Party Sales - Posting to COGS G/l

Hi All

I am facing a problem with Third Party Scenario

When a PR is generated out of the Sales order, the G/l selected is that of Inventory Posting. I need G/l that of COGS.

I have checked the settings for GBB--> VAX and the G/l. is that of COGS, while the G/l which is picked is that of BSX.

Could anybody inform me what must be wrong?

Helpful answers will be suitably rewarded

Regards