I am not able to get correct package for building firefox. here is the list of commands I ran.Thanks for your help.

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cat /etc/issue
Ubuntu 6.06.1 LTS \n \l

( I can't update my OS for legacy reasons. This is where we build )

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( I replaced my sources.list with following )
cat /etc/apt/sources.list

deb http://ppa.launchpad.net/ubuntu-mozilla-daily/ppa/ubuntu hardy main
deb-src http://ppa.launchpad.net/ubuntu-mozilla-daily/ppa/ubuntu hardy main

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gpg --keyserver subkeys.pgp.net --recv-key 247510BE && gpg --armor --export  247510BE | sudo apt-key add -

gpg: directory `/home/shkundap/.gnupg' created
gpg: new configuration file `/home/shkundap/.gnupg/gpg.conf' created
gpg: WARNING: options in `/home/shkundap/.gnupg/gpg.conf' are not yet active during this run
gpg: keyring `/home/shkundap/.gnupg/secring.gpg' created
gpg: keyring `/home/shkundap/.gnupg/pubring.gpg' created
gpg: requesting key 247510BE from hkp server subkeys.pgp.net
gpg: /home/shkundap/.gnupg/trustdb.gpg: trustdb created
gpg: key 247510BE: public key "Launchpad PPA for Ubuntu Mozilla Daily Build Team" imported
gpg: no ultimately trusted keys found
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
gpg: no ultimately trusted keys found
OK

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sudo apt-get update

Get:1 http://ppa.launchpad.net hardy Release.gpg [316B]
Get:2 http://ppa.launchpad.net hardy Release [16.0kB]
Get:3 http://ppa.launchpad.net hardy/main Packages [14B]
Get:4 http://ppa.launchpad.net hardy/main Sources [14B]
Fetched 16.4kB in 2s (5982B/s)
Reading package lists... Done

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sudo apt-get build-dep firefox


Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to find a source package for firefox
( here is my problem )
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