Actually, it is on of the few things that are easy in php.  I am fairly 
new to the unix world but I am getting there.  If you go to 
/usr/local/etc there is a php.ini file that you can edit.  There is a 
directive in that for register_global= on or off  .   To be safer you 
can add a .htaccess file to the directory of your auction site that has 
an override directive for php to turn them on.  They pose a bit of a 
security risk when they are on.