Add/Remove doesn't work, either does synaptic package manager.

[mykulz1]

There is a stop sign on the update manager icon in the top right of the toolbar. When I check for updates I get this error:

 E: Encountered a section with no Package: header
E: Problem with MergeList /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_jaunty-security_restricted_binary-i386_Packages
E: The package lists or status file could not be parsed or opened.
E: _cache->open() failed, please report.

Synaptic Package Manager has the same problem, Add/Remove comes up with this:

Failed to check for installed and available applications

This is a major failure of your software management system. Please check for broken packages with synaptic, check the file permissions and correctness of the file '/etc/apt/sources.list' and reload the software information with: 'sudo apt-get update' and 'sudo apt-get install -f'.

I also can't add programs using the terminal.

This is the error with Ubuntu Tweak:

Traceback (most recent call last):
  File "/usr/share/ubuntu-tweak/mainwindow.py", line 516, in setup_notebook
    page = page()
  File "/usr/share/ubuntu-tweak/installer.py", line 159, in __init__
    update_apt_cache(True)
  File "/usr/share/ubuntu-tweak/common/package.py", line 49, in update_apt_cache
    cache = apt.Cache(apt.progress.OpTextProgress())
  File "/usr/lib/python2.6/dist-packages/apt/cache.py", line 62, in __init__
    self.open(progress)
  File "/usr/lib/python2.6/dist-packages/apt/cache.py", line 75, in open
    self._cache = apt_pkg.GetCache(progress)
SystemError: E:Encountered a section with no Package: header, E:Problem with MergeList /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_jaunty-security_restricted_binary-i386_Packages, E:The package lists or status file could not be parsed or opened.

I am running Ubuntu Jaunty Jackalope 9.04.