RTEMS with virtual machine

[Asma Mehiaoui]

Hello,

I would like to install RTEMS with virtual machine, i download the image of 
Fedora with RTEMS "Fedora12-RTEMS-20100312.zip"
and i follow the steps in this page :
http://www.rtems.com/wiki/index.php/Virtual_Machines_for_RTEMS_Development
but when i tape ./bootstrap i have this error: 
configure.ac5: error: Autoconf version 2.86 or higher is required.
and when i try to install autoconf this message appear : Package autoconf 
-2.63-5 fc 12.noarch already installed and latest version
nothing to do

I need your help please