I don’t know how XP had it (never used it). But I have no problems typing different languages. Do you mean using different alphabets/scripts like हिन्दी ?
If you are using KDE, go to Configure Desktop>Regional and Language>Keyboard layout.
This allows you to activate different keyboard layouts and to have up to four different layouts installed between which you can switch using the flag icon which appears in your systray. This works in nearly every program.
In addition, if you are using OpenOffice Writer, each document starts with the default language unless you change that in the Configuration dialogue. But once you have chosen to include another language, a bar below the text appears indicating the current language; you can click on this to change the language being used.
If you have a dictionary installed for that language, it will spell check it. If not, it will ignore it for spell checking purposes. (This is also useful if you want to include spelling errors or unusual words which you don’t want in your personal dictionary - label them as Latin or any language for which you don’t have a dictionary and OpenOffice will ignore them).