Fix for incorrect Totals shown in Reports>Product>Purchased in OC1.5.6 (vQmod)
Works on default admin model file in OC 1.5.6 but should work in others so long as they don't mess with the admin files too much - test and report back please!
Install: Simply copy the vqmod folder to your shop's root directory (where you can see admin, catalog etc) - no core files are overwritten.
Remember to clear vQmod cache!
All this fix does is replace the total calculation code from the admin/model/report/product.php with one which calculates tax correctly.
EDIT: I have amended the code after ADD Creative and zilgrg pointed out a flaw in the sum, it should now be correct on sales of more than 1 item only - please download the new version 1.1 and use that instead.
If you want to hard code this fix just use the xml to show you what code to replace and what to replace it with :)