As promised, here's the extension to Uni-Library.

There are only two functions which might be useful for you:
One  can  transcode  a  plain  text (ASCII, ISO-8859-x, TIS-620, Amiga-1251,
UTF-8  (yep,  you read right :), UTF-16, UTF-32) to UTF-8 and the other from
UTF-8  to  one  that  uses  as target a singlebyte character encoding scheme
(ISO-8859-x, TIS-620, Amiga-1251).

The archive contains static libraries for Amiga m68k, MorphOS and Amiga PPC.
They were created using vbcc but should be also useable for users of gcc.
In  addition,  the source codes, which were used to form the static library,
have been enclosed.

A simple demo has been enclosed as well.