False Positive?

Info:

Browsing a vB site I run. We all YouTube videos to be embedded by certain users.

This popped up, I’m thinking it’s false.

http://img174.imageshack.us/img174/2452/avast2gw1.png

Edits:

OS: XP Pro fully patched, non-admin user
Browser: Firefox 1.5.0.7

Seems a false positive to Dr.Web Online URL verification: http://online.drweb.com/?url=1

But, maybe, it’s better to test any file (after download) against other on-line scanners.
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