Ensure that system environment variable PATH includes the location of all the compilers mentioned above.

Download the source code of ICU (in this example version 3.6 for C from http://icu.sourceforge.net/download/3.6.html#ICU4C).

At the shell prompt, run the following commands:

gunzip -d <  icu4c-3_6-src.tgz | tar -xf -
cd icu/source/
chmod +x runConfigureICU configure install-sh
runConfigureICU HP-UX/ACC --disable-threads
gmake
gmake check
gmake install

Set the environment variable LD_LIBRARY_PATH to point to the location of ICU. HP-UX uses the environment variable LD_LIBRARY_PATH to search for dynamically linked libraries.