I'm using Mandrake 9.1 and want to type Vietnamese so I installed a program called xvnkb at
ttp://visc-network.com/products/xvnkb.htm
However I am unable to get the unicode input to work. I am able to type using the other encodings. From what I understand I need to type

xvnkb
<my program>

and then just type in whatever I want, but it doesn't work for me. On the homepage I see a little note about using the unicode, but I ca'nt understand it. I want to use the telex input method to type unicode encoding. If it's done correctly, you can type in "aa" and it will return a letter "a" with a "^" on top.