No lzma sdk in fedora

[Bruno Wolff III]

On Fri, Feb 12, 2010 at 13:34:48 -0800,
  John Reiser <jreiser at bitwagon.com> wrote:
> > Another related note is that someone wanted a src package for it because
> > they had something that would only build with access to the source. I am
> > not planning on providing that, but wanted people to be aware we had a request
> > for it.
> 
> The package that needs the src is the upx package.  The coupling
> is very strong, therefore a physical copy of the entire specific
> version of lzma source was put into the source for Fedora's upx.
> The URL for that lzma source was recorded, but not used as a SourceN:.
> It is expected that the URL will become stale.

Do you think packaging that as a subpackage is worth while? A couple of other
packages seem to do that kind of thing?

Where is an appropriate location to put the source?

Is a buildrequires on a package that provides source allowed for packaging?