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.

 PERMSSN    UID  GID    PACKED    SIZE  RATIO METHOD CRC     STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[unknown]                 1362    1904  71.5% -lh5- a952 Jul 18 13:54 UniSupport.info
[unknown]                 1437    3260  44.1% -lh5- a877 Jul 18 13:54 UniSupport/html/copyright.html
[unknown]                  925    6056  15.3% -lh5- 711a Jul 18 13:54 UniSupport/html/GetMappingTable.html
[unknown]                  790    6345  12.5% -lh5- c5ef Jul 18 13:54 UniSupport/html/image/bg_big.png
[unknown]                  944    6084  15.5% -lh5- 88ac Jul 18 13:54 UniSupport/html/InitLocalHook.html
[unknown]                 1183    6607  17.9% -lh5- a5dd Jul 18 13:54 UniSupport/html/UniAccuUTF8StrLen.html
[unknown]                 1956    8649  22.6% -lh5- 1dbe Jul 18 13:54 UniSupport/html/UniConvertToUTF8.html
[unknown]                 1397    7149  19.5% -lh5- f62f Jul 18 13:54 UniSupport/html/UniFromUTF8ToSces.html
[unknown]                 1002    6288  15.9% -lh5- b312 Jul 18 13:54 UniSupport/html/UniLegalUTF8Boundary.html
[unknown]                 1229    3040  40.4% -lh5- 5b34 Jul 18 13:54 UniSupport/index.html
[unknown]                 2720    3387  80.3% -lh5- 1e78 Jul 18 13:54 UniSupport/index.html.info
[unknown]                 4996   11900  42.0% -lh5- eae7 Jul 18 13:54 UniSupport/lib/Amiga_m68k/unisupp.lib
[unknown]                 5032   11932  42.2% -lh5- a552 Jul 18 13:54 UniSupport/lib/Amiga_m68k/unisupps.lib
[unknown]                 5923   16090  36.8% -lh5- 9524 Jul 18 13:54 UniSupport/lib/Amiga_PPC/libunisupp.a
[unknown]                 5845   15726  37.2% -lh5- c3a1 Jul 18 13:54 UniSupport/lib/Amiga_PPC/libunisupps.a
[unknown]                 6071   16762  36.2% -lh5- 8a95 Jul 18 13:54 UniSupport/lib/MorphOS/libunisupp.a
[unknown]                 5966   16386  36.4% -lh5- 23cd Jul 18 13:54 UniSupport/lib/MorphOS/libunisupps.a
[unknown]                  670    1390  48.2% -lh5- 4495 Jul 18 13:54 UniSupport/proto/unisupport.h
[unknown]                 3151    8530  36.9% -lh5- 16e9 Jul 18 13:54 UniSupport/src/demo.c
[unknown]                  153     486  31.5% -lh5- a6dd Jul 18 13:54 UniSupport/src/makefile_all.bat
[unknown]                  768    1646  46.7% -lh5- 85f5 Jul 18 13:54 UniSupport/src/make_m68k_large
[unknown]                  773    1655  46.7% -lh5- a987 Jul 18 13:54 UniSupport/src/make_m68k_small
[unknown]                  958    2127  45.0% -lh5- 1e9a Jul 18 13:54 UniSupport/src/make_morphos_large
[unknown]                  962    2132  45.1% -lh5- 7a5b Jul 18 13:54 UniSupport/src/make_morphos_small
[unknown]                  975    2149  45.4% -lh5- 5fbb Jul 18 13:54 UniSupport/src/make_ppc_amiga_large
[unknown]                  979    2154  45.5% -lh5- b135 Jul 18 13:54 UniSupport/src/make_ppc_amiga_small
[unknown]                  944    1936  48.8% -lh5- c0e2 Jul 18 13:54 UniSupport/src/mapping_table.h
[unknown]                 4921   32309  15.2% -lh5- 5abb Jul 18 13:54 UniSupport/src/mapping_tables.c
[unknown]                 1954    4578  42.7% -lh5- 2ef3 Jul 18 13:54 UniSupport/src/uni_accustr.c
[unknown]                 1885    4274  44.1% -lh5- 9e04 Jul 18 13:54 UniSupport/src/uni_boundary.c
[unknown]                 1728    3795  45.5% -lh5- 7595 Jul 18 13:54 UniSupport/src/uni_hooks.c
[unknown]                 1425    4569  31.2% -lh5- 6161 Jul 18 13:54 UniSupport/src/uni_iana_to_table.c
[unknown]                 1291    2642  48.9% -lh5- 5077 Jul 18 13:54 UniSupport/src/uni_local_protos.h
[unknown]                 2369    5272  44.9% -lh5- dd63 Jul 18 13:54 UniSupport/src/uni_to_sces.c
[unknown]                 4168   11973  34.8% -lh5- bc5a Jul 18 13:54 UniSupport/src/uni_to_utf8.c
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total        35 files   78852  241182  32.7%            Jul 19 09:25