xz branch for EL-4

[David Rees <drees76 gmail com>]

I see that xz is available for EL-5, but not for EL-4.  Would it be
possible to branch xz for EL-4 as well?

It would be useful to have that utility available there as well.  I
did try downloading the el.5 source rpm, but it has a dependency on xz
which keeps me from trying to build it there.

FWIW, the upstream source did compile OK on an EL-4 machine I have.

Thanks!

Dave