[asterisk-users] Upgrade Procedure

[Nitesh Divecha]

Hello All,

I would like to upgrade my recently installed Asterisk 1.2.21.1 to 
Asterisk 1.4.8?

My OS is CentOS 4.5 with Linux 2.6.9-55.0.2.plus.c4smp #1 SMP Fri Jul 6 
05:25:07 EDT 2007 i686 i686 i386 GNU/Linux

Is there any detail step by step procedure to uninstall the current 
version and install Asterisk 1.4.8, Zaptel 1.4.4, Libpri 1.4.1, Addons 
1.4.2?

Cheers,
Nitesh