Possible Bug in DI with Gross Profit? Please confirm.

Question

The following works:
1) Add an Inventory Item and set the "Items per Sales Unit" field to "0.1". The "Items per Purchase Unit" is set to "1".
2) Create a goods receipt for 1 purchase unit.
3) Create an A/R invoice for 1 unit.
This should add a line item for 0.1 inventory units and set the price to 0.1 * <itemprice> which it does.
4) Click on the Gross Profit money bag and everything displays correctly. The journal entry for COGS is also correct.
What doesn't work:
If you try the above using the DI API then the journal entry for COGS is correct, but when you find the A/R invoice and click the gross profit money bag then it shows that you sold the item at a loss since it uses the full purchase price unit vs the partial sales unit.
If you then go an manually add an A/R invoice for the item added through DI API then gross profit calculates correctly.
There seems to be a problem with the gross profit when you add the invoice through DI API. Is there a parameter when adding SO or AR Invoices that I could be missing?
System Info:
SBO 2005 A (6.80.123)
SQL Server
Document Settings > Base Price Origin set to Item Cost

Answer 1

More information:
After further research I found that the DI API is setting the unit to the Sales Unit (which is correct), but it sets the price to the Inventory Unit price.
When I set the price via the DI API to what it should be then the discount column was set to 90%.
Is this by design? If so, what do I need to do to correct this problem?