Ambiguous output redirect

[bsd]

I don't understand why when I execute this script I have an  
"Ambiguous output redirect." ?


p0f -l 'tcp dst port 25' 2>&1 | /usr/local/sbin/p0f-analyzer.pl 2345 &



Can you help ?

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Gregober ---> PGP ID --> 0x1BA3C2FD
bsd @at@ todoo.biz
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