Comment 2 for bug 892855

This is not a bug. When you use dpkg to install a package, it does not pull in the package dependencies; you need to manually install them, or run 'apt-get -f install' after calling dpkg, or use a higher-level tool (such as Software Center) for installing the package.

Furthermore, the 32-bit gtalk plugin package will not integrate with a 64-bit desktop anyway because it provides a 32-bit plugin and a 64-bit plugin (or integration with nspluginwrapper) is needed to make the package usable with a 64-bit browser. That's not a bug in Ubuntu, it's a limitation of the package in question. You need to install the amd64 gtalk plugin package instead.