I also have this in the activity log:

Risk category: Heuristic Virus
Overall Risk Impact: High
Performance: High
Privacy: High
Removal: High
Stealth: High
Click for more information about this risk : Bloodhound.PDF.1
Action taken: Blocked
Affected Areas: c:\documents and settings\adam\local settings\application data\mozilla\firefox\profiles\ds26j6zp.default\cache\e887b5d0d01