Multilingual issues = different localization ?

As many of you I don't belong to Anglo-Saxon world.
I a Swede studying Slavic languages - it means - that I am word processing and using spreadsheets with in those languages. Hoping that the linguistic integrity of the files will be preserved.
Entering different foreign characters seamlessly is into AbiWord is as I understand not possible. You have to restart for each for each language that differs from preceding one. What about OpenOffice Portable ? Is different localization possible in a portable world ?

brennos