XeTeX is Unicode-based TeX using platform fonts and font technologies (e.g. AAT on Mac OS X or OpenType features on Mac/Linux/Windows) to provide typesetting for all the world's scripts.
UPMS is based on BSD ports system, it can be used on any FSH 2.x Linux compatible distribution. UPMS have two level of dependencies checking, required and suggested. This two levels makes UPMS to tune all of the packages to optimal or minimal, depend on