If you want to help to translate quassel to your language, here is a quick howto.
See Translating/German for further information.
In order to create or update a translatable file, run the following command in the directory i18n/:
lupdate ../src -ts quassel_xx.ts -no-obsolete
where xx is the two-letter language code according to ISO 639 (which, if needed, may be suffixed by a country code according to ISO 3166).
HINT: In Kubuntu it's in the qt4-dev-tools package and you should use lupdate-qt4
Quassel will automatically load these translation files based on the system locale. Examples for valid file names:
You can open these XML files with the Qt Linguist and add/edit translated strings.
The *.ts files can and should be kept in sync with the source code by running lupdate regularly (existing translations won't be removed).
Qt itself does not use the .ts files, but a compact binary format (.qm). These files will automatically be generated at build time. By default, all
languages will be built. To select languages, add -DLINGUAS="<languages>" to your cmake call, where <languages> is a space-separated list of language
codes as explained above.
NOTE: You'll need lrelease installed with your Qt in order to generate
translation files. Some distributions don't package that tool;
in that case you won't get translations.
This is directly copied from the README file inside the i18n directory.