There's a possibility it may be nothing:
http://www.phpbb.com/community/viewt...p?f=1&t=797915
Also be aware that some AV software will report a link as a trojan.
If the link is to a known source of malware a lot of AV software is set to 'know' those links and report it.
It would not mean that your site is infected, only that someone has posted a link to a place that is.
As an anti-malware fighter (and forum owner) I come accross this sort of thing a lot.
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