Installation of dahdi and freepbx

Hi all…

I am fresh here…

  1. I am facing a problem when installing dahdi. I updated the kernel also.
    The error shows like as follows:

You do not appear to have the source for the 2.6.18-92.el5PAE kernel installed.
make[1]: ***[modules]Error 1
make[1]: Leaving directory /usr/src/asterisk/dahdi-linux-complete-
make[2]: ***[all]Error 2

  1. When I am trying to install freepbx:

Checking if Asterisk is running…sh: /pidof: No such file or directroy
[FATAL] ./install_amp
Asterisk must be running. If this is a first time install, you should start Asterisk by
typing './start_asterisk start’
For upgrading you should run ‘amportal start’

Can any one having the solution for this?
Please help…
and thanking you all in advance