You came to the right place.
Any threat labelled as Bloodhound is detected using the heuristic scanning engine by Symantec.
Details of the threat can be found here:
http://www.symantec.com/security_response/writeup.jsp?docid=2011-050208-1645-99
It explains that it could be a variant of Bloodhound.Oleswf whcih can be found here:
http://www.symantec.com/security_response/writeup.jsp?docid=2011-040110-3607-99
If you could submit the sample, you might get a better solution. You may also have set the Bloodhound level to high. Does all Twitter users experience this or is it limited to a few who could be following users that post infected Flash objects/hyperlinks?