We've now encountered the same problem, in AcadE 2013.
It ONLY appears if we run the BOM-report with the "Display in Tallied Purchase List Format". All the other three options lists the Manufacturer in a combination of upper/lower case letters.
About time to fix this Autodesk?
THL Please select "Accept As Solution" if this post answers your question. Kudos don't hurt either. ;-)
