Put different languages from different langpacks

Hi,

I've heard that its possible to put different languages from different languagepacks in 1 phone, it should take time i heard.. but how can i do that?

For example, i want to put arabic and swedish together but they're actually from different language packs (EMEA6 and EUROPE4).

i have a k510i and moving to sweden and need to change to europe 4 how can i do it??? i cannot download from this site yet as im a noob.... pls someone help a brother out??/