package flashplugin-installer (not installed) failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[DrX]

Error 404 in Ubuntu repositories "File not found" when trying to install package. Ubuntu 12.04 Beta

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: flashplugin-installer (not installed)
ProcVersionSignature: Ubuntu 3.2.0-16.25-generic 3.2.6
Uname: Linux 3.2.0-16-generic i686
ApportVersion: 1.91-0ubuntu1
AptOrdering: flashplugin-installer: Configure
Architecture: i386
Date: Fri Mar 2 22:29:24 2012
DpkgHistoryLog:
 Start-Date: 2012-03-02 22:29:20
 Commandline: apt-get upgrade
ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Beta i386 (20110330)
SourcePackage: flashplugin-nonfree
Title: package flashplugin-installer (not installed) failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: Upgraded to precise on 2012-03-03 (0 days ago)