i18n questions

[M . Reck]

Hi all,
I am trying to develop a multilingual site by use of the i18n-Transformer.
But some questions arise:
1. Is it possible to have the translations for all languages in the same one file? I mean one file per site.
2. Where do I have to put the dictionary and how do I call it from the xml-file resp. xsl-file?
3. Why is there no dictionary.xml file in the i18n sample, but instead messages(_locale).xml files whose contents is quite different from the example for the dictionary entry in the documentation of the i18n transformer?

Any help is very much appreciated!

Martina