"xz" extension problem

[GoogleCodeExporter]

Files with "xz" extensions seem not to be installed with apt-cyg

What steps will reproduce the problem?
1. fresh install cygwin with default plus wget
2. try installing LibXpm4
3. get error "bunzip2: (stdin) is not a bzip2 file."

What is the expected output? What do you see instead?
packages should be installed without this error

What version of the product are you using? On what operating system?
v0.58

Please provide any additional information below.

Original issue reported on code.google.com by yilmaz.d...@gmail.com on 10 Jul 2014 at 12:53