This is pdfTeX, Version 3.1415926-1.40.10 (TeX Live 2009/Debian) (format=pdflatex 2010.8.25)  3 NOV 2010 02:18
entering extended mode
 restricted \write18 enabled.
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**comba2.tex
(./comba2.tex
LaTeX2e <2009/09/24>
Babel <v3.8l> and hyphenation patterns for english, usenglishmax, dumylang, noh
yphenation, loaded.

! LaTeX Error: File `sig-alternate.cls' not found.

Type X to quit or <RETURN> to proceed,
or enter new name. (Default extension: cls)

Enter file name: x

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(\end occurred when \ifx on line 2 was incomplete)
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 210 string characters out of 1182621
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 3640 words of font info for 14 fonts, out of 3000000 for 9000
 28 hyphenation exceptions out of 8191
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