Description:
------------
ereg wrongly indicates that a GET string contains only integers if the string is first processed using utf8_decode. 

Example: The regular expression should return true only if the variable 'tt' in the GET string contains between 1 and 8 number characters. 

This behaves correctly:
ereg('^[0-9]{1,8}$',$_GET['tt']))

This behaves wrongly:
ereg('^[0-9]{1,8}$',utf8_decode($_GET['tt'])))
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PHP Configure line - './configure' '--with-apxs2=/usr/local/apache/bin/apxs' '--with-mysql=/usr/local/mysql/' '--with-mysql-sock=/tmp/mysql.sock' '--enable-exif' '--with-gd' '--with-jpeg-dir=/usr/lib' '--with-png-dir=/usr/lib' '--with-zlib-dir=/usr/lib' '--with-xpm-dir=/usr/lib' '--with-freetype-dir=/usr/lib' '--with-t1lib=/usr/lib' '--with-freetype-dir=/usr/lib' '--disable-debug' '--with-config-file-path=/etc/httpd' '--with-openssl=/usr/local/ssl' '--enable-memory-limit'
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Apache 2.0.49
core mod_access mod_auth mod_include mod_log_config mod_env mod_headers mod_setenvif mod_ssl prefork http_core mod_mime mod_status mod_autoindex mod_asis mod_cgi mod_negotiation mod_dir mod_imap mod_actions mod_alias mod_so mod_expires mod_rewrite mod_deflate mod_logio sapi_apache2 mod_security

Reproduce code:
---------------
Call this script with the following line in the browser:

http://localhost/test.php?tt=119%f0

<?php
if(isset($_GET['tt']) && eregi('^[0-9]{1,8}$',utf8_decode($_GET['tt']))){
  //Should only get here if 'tt' is an integer 
  echo 'Integer';
}else{
  echo 'Not an integer';
}
?>

Expected result:
----------------
The script should return "Not an integer" in the browser.

Actual result:
--------------
The script returns "Integer" in the browser, even though the GET string contains other characters.