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Lord_Majestic - 6:54 pm on Jun 23, 2009 (gmt 0)
Such URLs called "dangling links" in PageRank algorithm. They don't need to be indexed in order to have PageRank, however they DO need to have outgoing urls (and thus indexed) if they were to pass PageRank further.
Since the file types you mention are not indexed, they wouldn't actually receive any PageRank