La génération automatique d'affiche a rencontré un problème:
This is pdfTeXk, Version 3.141592-1.40.3 (Web2C 7.5.6)
 %&-line parsing enabled.
entering extended mode
(/tmp/poster.tex
LaTeX2e <2005/12/01>
Babel  and hyphenation patterns for english, usenglishmax, dumylang, noh
yphenation, arabic, basque, bulgarian, coptic, welsh, czech, slovak, german, ng
erman, danish, esperanto, spanish, catalan, galician, estonian, farsi, finnish,
 french, greek, monogreek, ancientgreek, croatian, hungarian, interlingua, ibyc
us, indonesian, icelandic, italian, latin, mongolian, dutch, norsk, polish, por
tuguese, pinyin, romanian, russian, slovenian, uppersorbian, serbian, swedish, 
turkish, ukenglish, ukrainian, loaded.
(/usr/share/texmf/tex/latex/base/article.cls
Document Class: article 2005/09/16 v1.4f Standard LaTeX document class
(/usr/share/texmf/tex/latex/base/size11.clo))
(/usr/share/texmf/tex/latex/base/inputenc.sty
(/usr/share/texmf/tex/latex/base/latin1.def))
(/usr/share/texmf/tex/generic/babel/babel.sty
(/usr/share/texmf/tex/generic/babel/frenchb.ldf
(/usr/share/texmf/tex/generic/babel/babel.def)
*************************************
* Local config file frenchb.cfg used
*
(/usr/share/texmf/tex/generic/babel/frenchb.cfg))) (./poster.aux)
(/usr/share/texmf/tex/latex/lm/t1lmr.fd)
! Misplaced alignment tab character &.
 ...ma \@parboxrestore \begin {center}S&
                                                  eacute;minaire de physique...
l.41 }
      
? 
! Emergency stop.
 ...ma \@parboxrestore \begin {center}S&
                                                  eacute;minaire de physique...
l.41 }
      
No pages of output.
Transcript written on poster.log.

Si vous en avez la possibilité, merci de bien vouloir corriger les informations erronées.