My prayer to he code gods :
I report exactly the same problem, also using 64bit Ubuntu (8.10 in this case) and the same repository. WXWidgets is also up to date.
Completely uninstalling, purging and reinstalling WXWidgets and Code::Blocks from an installation file did not have the desired effect, i am still unable to open or create ANY projects, causing Code::Blocks to be completely useless.
I attached the bug report XML which is generated when trying to create a new project. Trying to open existing projects or workspaces does not cause a bug report, however, it just states that opening the files isn't possible.
I guess that i got no other choice than using some other IDE until a solution or fix is around, last time i checked though there weren't too many decent ones around that worked on 64bit. =(
EDIT :
I disabled the svn build repository
http://lgp203.free.fr/ubuntu/ , deinstalled and reinstalled codeblocks again. It now uses the version 8-02ubuntu2 from the standard repositories. That might be an older version, but at least it works again.
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