Merci pour ta réponse !
je tourne sous fedora core, voila la page concerné : http://www.mayattitude.com/send_sauv.php sinon j'ai trouvé un rapport d'erreur qui me parait interessant, ca viendra du mod_security :
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HTTP/1.1 404 Not Found
Content-Length: 329
Keep-Alive: timeout=15, max=99
Connection: Keep-Alive
Content-Type: text/html; charset=iso-8859-1
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Apache-Error: [file "/builddir/build/BUILD/httpd-2.2.6/server/core.c"] [line 3633] [level 3] File does not exist: /var/www/html/favicon.ico
Stopwatch: 1203692015424522 10901 (760 8904 -)
Producer: ModSecurity v2.1.3 (Apache 2.x)
Server: Apache/2.2.6 (Fedora)
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--52357a78-A--
[22/Feb/2008:15:53:38 +0100] Yy7t1n8AAAEAACMoZjkAAAAB 192.168.1.10 4648 192.168.1.12 80
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POST /send.php?sendid=1 HTTP/1.1
Host: www.xxxx
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; fr; rv:1.8.1.12) Gecko/20080201 Firefox/2.0.0.12
Accept: text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Language: fr,fr-fr;q=0.8,en-us;q=0.5,en;q=0.3
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://www.xxx/send.php
Content-Type: application/x-www-form-urlencoded
Content-Length: 50
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pseudo=%E9%E9%E9%E9&message=%E9&submit=Envoyer+%21
--52357a78-F--
HTTP/1.1 400 Bad Request
Content-Length: 346
Connection: close
Content-Type: text/html; charset=iso-8859-1
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Message: Access denied with code 400 (phase 2). Invalid Unicode encoding: invalid byte value in character. [id "950801"] [msg "UTF8 Encoding Abuse Attack Attempt"] [severity "WARNING"]
Action: Intercepted (phase 2)
Stopwatch: 1203692018527702 3544 (1009* 1897 -)
Producer: ModSecurity v2.1.3 (Apache 2.x)
Server: Apache/2.2.6 (Fedora)
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