https://sourceforge.net/tracker/?func=detail&aid=2800967&group_id=176962&atid=879332

- Initial cost from m_product_po is wrong if m_product_po.c_uom_id <> m_product.c_uom_id
- fixed a typo error: should be i instead of 0
- Need to do checking after uom conversion

base/src/org/compiere/model/MCost.java

@@ -400,6 +400,9 @@ public class MCost extends X_M_Cost
 						price = MUOMConversion.convertProductTo (Env.getCtx(), product.getM_Product_ID(),
 								pos[i].getC_UOM_ID(), price);
 					}
+				}
+				if (price != null && price.signum() != 0)
+				{
 					retValue = price;
 					s_log.fine(product.getName() + ", Product_PO = " + retValue);
 					return retValue;