Note that the point releases of 10.04 are just roll-ups of the packages from the
updates archives. If you have been regularly applying the updates to your server (which is the recommended behaviour), you are probably already at the new point release.
If you have upgraded to a package that is causing you problems, you can downgrade a package. You can discover what versions of a package are available with the following command:
apt-cache policy PACKAGE_NAME
Note the version numbers it lists for each archive. You can install a specific version of a package with the following command:
sudo apt-get install PACKAGE_NAME=VERSION_NUMBER
You will be warned that you are downgrading the package.