cannot install democracyplayer in ubuntu 7.04

lets try it with good old aptitude....from a terminal

sudo aptitude install democracyplayer
sudo aptitude -f install
sudo aptitude install libxine-extracodecs

pyan@pyan-laptop:~$ sudo aptitude install democracyplayer
Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading extended state information
Initializing package states... Done
Building tag database... Done
The following packages are BROKEN:
  democracyplayer firefox-dev
The following NEW packages will be automatically installed:
  mozilla-browser mozilla-dev mozilla-psm
The following packages will be automatically REMOVED:
  libnspr-dev libnss-dev
The following NEW packages will be installed:
  democracyplayer-data mozilla-browser mozilla-dev mozilla-psm
The following packages will be REMOVED:
  libnspr-dev libnss-dev
0 packages upgraded, 5 newly installed, 2 to remove and 0 not upgraded.
Need to get 14.4MB/14.9MB of archives. After unpacking 64.1MB will be used.
The following packages have unmet dependencies:
  democracyplayer: Depends: python (< 2.5) but 2.5.1~rc1-0ubuntu3 is installed.
  firefox-dev: Depends: libnss-dev (= 2:1.firefox2.0.0.3+1-0ubuntu2) but it is not installable
               Depends: libnspr-dev (= 2:1.firefox2.0.0.3+1-0ubuntu2) but it is not installable
Resolving dependencies...
The following actions will resolve these dependencies:

Keep the following packages at their current version:
democracyplayer [Not Installed]
libnspr-dev [2:1.firefox2.0.0.3+1-0ubuntu2 (feisty, now)]
libnss-dev [2:1.firefox2.0.0.3+1-0ubuntu2 (feisty, now)]
mozilla-dev [Not Installed]

Score is -9970

Accept this solution? [Y/n/q/?] y
WARNING: untrusted versions of the following packages will be installed!

Untrusted packages could compromise your system's security.
You should only proceed with the installation if you are certain that
this is what you want to do.

  mozilla-psm democracyplayer-data mozilla-browser

Do you want to ignore this warning and proceed anyway?
To continue, enter "Yes"; to abort, enter "No": yes
The following NEW packages will be automatically installed:
  mozilla-browser mozilla-psm
The following NEW packages will be installed:
  democracyplayer-data mozilla-browser mozilla-psm
0 packages upgraded, 3 newly installed, 0 to remove and 0 not upgraded.
Need to get 10.2MB/10.6MB of archives. After unpacking 33.1MB will be used.
Do you want to continue? [Y/n/?] y
WARNING: untrusted versions of the following packages will be installed!

Untrusted packages could compromise your system's security.
You should only proceed with the installation if you are certain that
this is what you want to do.

  mozilla-psm democracyplayer-data mozilla-browser

Do you want to ignore this warning and proceed anyway?
To continue, enter "Yes"; to abort, enter "No": yes
Writing extended state information... Done
Get:1 http://my.archive.ubuntu.com edgy/universe mozilla-browser 2:1.7.13-0.2ubuntu1 [10.0MB]
Get:2 http://my.archive.ubuntu.com edgy/universe mozilla-psm 2:1.7.13-0.2ubuntu1 [180kB]
Fetched 10.2MB in 24m50s (6851B/s)
Preconfiguring packages ...
Selecting previously deselected package democracyplayer-data.
(Reading database ... 199826 files and directories currently installed.)
Unpacking democracyplayer-data (from .../democracyplayer-data_0.9.5.1-1ubuntupcf_all.deb) ...
Selecting previously deselected package mozilla-browser.
Unpacking mozilla-browser (from .../mozilla-browser_2%3a1.7.13-0.2ubuntu1_i386.deb) ...
Selecting previously deselected package mozilla-psm.
Unpacking mozilla-psm (from .../mozilla-psm_2%3a1.7.13-0.2ubuntu1_i386.deb) ...
Setting up democracyplayer-data (0.9.5.1-1ubuntupcf) ...
Setting up mozilla-browser (1.7.13-0.2ubuntu1) ...
Updating mozilla chrome registry...done.

Setting up mozilla-psm (1.7.13-0.2ubuntu1) ...
Updating mozilla chrome registry...done.

pyan@pyan-laptop:~$ sudo aptitude -f install
Password:
Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading extended state information
Initializing package states... Done
Writing extended state information... Done
Building tag database... Done
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0B of archives. After unpacking 0B will be used.
Writing extended state information... Done
pyan@pyan-laptop:~$ sudo aptitude install libxine-extracodecs
Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading extended state information
Initializing package states... Done
Building tag database... Done
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0B of archives. After unpacking 0B will be used.
Writing extended state information... Done

after i wrote in terminal:
sudo aptitude install democracyplayer
sudo aptitude -f install
sudo aptitude install libxine-extracodecs
i open Synaptic Package Manager and i'm trying to install democracyplayer this message appeared:
democracyplayer:
  Depends: python (<2.5) but 2.5.1~rc1-0ubuntu3 is to be installed

Can i see a copy of your /etc/apt/sources.list

We can fix this unless you have some compelling reason for having python release candidates installed?

pyan@pyan-laptop:~$ cat /etc/apt/sources.list

# deb cdrom:[Ubuntu 6.10 _Edgy Eft_ - Release i386 (20061025)]/ edgy main restricted

## Major bug fix updates produced after the final release of the
## distribution.

## Uncomment the following two lines to add software from the 'universe'
## repository.
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## universe WILL NOT receive any review or updates from the Ubuntu security
## team.
deb http://my.archive.ubuntu.com/ubuntu/ edgy universe
deb-src http://my.archive.ubuntu.com/ubuntu/ edgy universe

## Uncomment the following two lines to add software from the 'backports'
## repository.
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
# deb http://my.archive.ubuntu.com/ubuntu/ edgy-backports main restricted universe multiverse
# deb-src http://my.archive.ubuntu.com/ubuntu/ edgy-backports main restricted universe multiverse

deb http://security.ubuntu.com/ubuntu edgy-security universe
deb-src http://security.ubuntu.com/ubuntu edgy-security universe

#AUTOMATIX REPOS START

deb http://archive.ubuntu.com/ubuntu feisty-backports main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu feisty-security main restricted universe multiverse

deb http://wine.lowvoice.nl/apt feisty main

deb http://www.getautomatix.com/apt feisty main

deb http://archive.canonical.com/ubuntu feisty-commercial main

#AUTOMATIX REPOS END
deb http://ftp.osuosl.org/pub/pculture.org/democracy/linux/repositories/ubuntu edgy/
deb http://archive.ubuntu.com/ubuntu/ feisty main universe restricted multiverse
deb-src http://archive.ubuntu.com/ubuntu/ feisty main universe restricted multiverse #Added by software-properties
deb http://security.ubuntu.com/ubuntu/ feisty-security universe main multiverse restricted
deb-src http://security.ubuntu.com/ubuntu/ feisty-security universe main multiverse restricted #Added by software-properties
deb http://archive.ubuntu.com/ubuntu/ feisty-updates universe main multiverse restricted
deb-src http://archive.ubuntu.com/ubuntu/ feisty-updates universe main multiverse restricted #Added by software-properties
pyan@pyan-laptop:~$

What was the outcome after looking at the source list?
I have the same problem. Waiting for the resolution of your problem.