From you comment:
"libxfixes3: Installed: 1:4.0-0ubuntu1 Candidate: 1:4.0-0ubuntu1 Version table: *** 1:4.0-0ubuntu1 0 100 /var/lib/dpkg/status 1:3.0.1.2-0ubuntu3 0 500 http://au.archive.ubuntu.com dapper/main Packages"
Which means that dapper has "1:3.0.1.2-0ubuntu3" and that you installed "1:4.0-0ubuntu1" from somewhere. That's not an Ubuntu bug, you probably want to stick to official packages for the version of the distribution
From you comment:
"libxfixes3: dpkg/status 3.0.1.2- 0ubuntu3 0 au.archive. ubuntu. com dapper/main Packages"
Installed: 1:4.0-0ubuntu1
Candidate: 1:4.0-0ubuntu1
Version table:
*** 1:4.0-0ubuntu1 0
100 /var/lib/
1:
500 http://
Which means that dapper has "1:3.0. 1.2-0ubuntu3" and that you installed "1:4.0-0ubuntu1" from somewhere. That's not an Ubuntu bug, you probably want to stick to official packages for the version of the distribution