package icedtea-6-jre-cacao (not installed) failed to install/upgrade: icedtea-6-jre-cacao: 6b24-1.11.1-4ubuntu2 (Multi-Arch

software center error because this issue...

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: icedtea-6-jre-cacao (not installed)
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14
Uname: Linux 3.2.0-24-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.0.1-0ubuntu7
Architecture: amd64
Date: Mon May 7 15:16:03 2012
DuplicateSignature:
 Unpacking openjdk-6-jre (from .../openjdk-6-jre_6b24-1.11.1-4ubuntu2_amd64.deb) ...
 dpkg: error processing /var/cache/apt/archives/icedtea-6-jre-cacao_6b24-1.11.1-4ubuntu2_amd64.deb (--unpack):
  icedtea-6-jre-cacao: 6b24-1.11.1-4ubuntu2 (Multi-Arch: same) is not co-installable with icedtea-6-jre-cacao:i386 6b18-1.8-0ubuntu1 (Multi-Arch: no) which is currently installed
ErrorMessage: icedtea-6-jre-cacao: 6b24-1.11.1-4ubuntu2 (Multi-Arch
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120423)
SourcePackage: openjdk-6
Title: package icedtea-6-jre-cacao (not installed) failed to install/upgrade: icedtea-6-jre-cacao: 6b24-1.11.1-4ubuntu2 (Multi-Arch
UpgradeStatus: No upgrade log present (probably fresh install)