Problem was solved after replacing linux kernel: upgraded from
2.6.38-2-amd64 to 2.6.39-1-amd64.
Peoples on forum report that 2.6.38-1-amd64 does not have this
Looks like problem appears while smplayer tries to fork mplayer.
Either it is 2.6.38-2-amd64 bug or smplayer bug which is triggered by
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