tedster - 3:59 pm on Jan 5, 2011 (gmt 0)
the link is only present in another site. It is beyond my control
That can be valuable information for a webmaster. Perhaps the link was intended for a page you removed, or represents a common typo.
In those cases, as meelosh mentioned, you might well want to collect the ranking power of that backlink - webmasters sometimes call this "link reclamation." Otherwise, you can safely ignore the 404 report. It's just there as an FYI.