Submit the file ie deactivate real time scanning and unquarantine the file zip it up and password protect it as mentioned in the below link and submit it to Mcafee.
When they reply (should be immediate reply to teh email changing the subject to possible false +ve and name of detyection
say where the file came from and see what Mcafee says. If no answer in 4 days post back here with teh analysis id from the reply email and I will get it checked.
Oh reactivate real time scanning do not forget to do this.....