The xz command is a very powerful program for compressing files.
* Average compression ratio of LZMA is about 30% better than that of
gzip, and 15% better than that of bzip2.
* Decompression speed is only little slower than that of gzip, being
two to five times faster than bzip2.
* In fast mode, compresses faster than bzip2 with a comparable
compression ratio.
* Achieving the best compression ratios takes four to even twelve
times longer than with bzip2. However. this doesn't affect
decompressing speed.
* Very similar command line interface to what gzip and bzip2 have.

this package was copied over from openSUSE:11.2
and some mods to fix build for SLE_10 (no autoreconf)