Initialization of update-manager fails

[Tiefflieger]

Binary package hint: update-manager

Appeared on up-to-date 64bit intrepid

when I try to start the update-manager, its window shows up and the loading-gauge starts working, just as usual. But then it comes up with the following (first I will give the version in english I've translated myself, then the version in german that actually was displayed )
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Package informations could not be initialized

A unrecoverable problem has occured during initialization of package information.

Report the error of »update-manager« and include following information in your report:

'E:Great, You have exceeded the number of descriptions APT is able to handle., E:Problem with MergeList /var/lib/apt/lists/ddebs.ubuntu.com_dists_intrepid_universe_binary-amd64_Packages, E:The package list or the status file could not be parsed or opened.'
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Paketinformationen konnten nicht initialisiert werden

Ein unlösbares Problem ist während der Initialisierung der Paketinformation aufgetreten.

Melden Sie eine Fehler im »update-manager« und fügen Sie die folgende Fehlermeldung in den Fehlerbericht ein:

'E:Toll, Sie haben die Anzahl an Beschreibungen überschritten, die APT handhaben kann., E:Problem with MergeList /var/lib/apt/lists/ddebs.ubuntu.com_dists_intrepid_universe_binary-amd64_Packages, E:Die Paketliste oder die Statusdatei konnte nicht geparst oder geöffnet werden.'
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I attached my /etc/apt/sources.list . I think (absolutely not for sure!) that my problem started when I wanted to obtain a backtrace of totem according to https://wiki.ubuntu.com/DebuggingProgramCrash.

[Michele Mangili (mangilimic)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. You reported this bug a while ago and there hasn't been any activity in it recently. We were wondering if this is still an issue for you. Can you try with the latest Ubuntu release?

At the same time I think that it might be useful attach to this bug report '/var/lib/apt/lists/ddebs.ubuntu.com_dists_intrepid_universe_binary-amd64_Packages' .

Thanks in advance.