I had to gather this information internally and have seen some recent questions in social forums around languages for Server and the multiple clients offered. 

February 1, 2011 Update – Jens has a guest post from Thomas Binder entitled:    Where is my localized device update?

 

Language Server Phone Attendant Client, MUI Attendee, no MUI
Arabic        x x
Brazilian Portuguese  x x x x x
Bulgarian        x x
Catalan*       x x
Chinese (Simplified)  x x x x x
Chinese (Traditional)  x x x x x
Croatian        x x
Czech        x x
Danish    x x x x
Dutch    x x x x
Estonian        x x
Finnish Finland   x x x x
French x x x x x
German x x x x x
Greek        x x
Hebrew        x x
Hindi        x x
Hungarian        x x
Italian x x x x x
Japanese x x x x x
Kazakh       x x
Korean x x x x x
Latvian        x x
Lithuanian        x x
Norwegian    x x x x
Polish        x x
Portuguese        x x
Romanian        x x
Russian    x x x x
Serbian (Latin)        x x
Slovak        x x
Slovenian        x x
Spanish x x x x x
Swedish    x x x x
Thai        x x
Turkish        x x
Ukrainian        x x

Catalan is a Language Interface Pack (LIP)- The product interface (UI) is in Catalan, the help (UA) is in Spanish

TomL MonolingualKid