bzip2 prints to stderr instead of stdout

[Steve Ward]

Binary package hint: bzip2

lsb_release -rd
Description: Ubuntu 10.04.1 LTS
Release: 10.04

apt-cache policy bzip2
bzip2:
  Installed: 1.0.5-4
  Candidate: 1.0.5-4
  Version table:
 *** 1.0.5-4 0
        500 http://us.archive.ubuntu.com/ubuntu/ lucid/main Packages
        100 /var/lib/dpkg/status

Run bzip2 with any option to print to the console. For example: "bzip2 --version" or "bzip2 --help". Redirect stdout to /dev/null, or use strace to see which file descriptor is being written to.

Expected result:
bzip2 prints to stdout.

Actual result:
bzip2 prints to stderr.

These compression utilities behave as expected:
gzip
lzma
lzip
xz
rzip
lzop