pclcomp originally came from this comp.sources.misc posting:
http://gatekeeper.dec.com/pub/usenet/comp.sources.misc/volume25/pclcomp/

While it doesn't contain a formal license, it does say:
"You may use parts of this code within your drivers to support compression
if you wish."

Under copyright law, you only have rights which are explicitly granted
in the license text.  Rights are not implicit.  Vague statements made
in email concerning code usage, generally aren't legally binding from
what I've been told by legal councel in the past.

I think it would be best for X.Org to avoid legal problems by contacting
the author and trying to get a proper relicensing for this, or alternatively
dropping it from the tree.

We don't ship this program in binary form, however in the monolithic tree,
it's in the source which is a bit disturbing.

The copyright owner is HP, so I'm adding HP's Xorg rep to the cc.

we have never shipped pclcomp as part of any release.  it was added to satisfy
bug #631, and the commit was not done on the 6.8 branch but on HEAD leading up
to 6.9.

unless we get a clear statement from hp on the licensing, this should be dropped
from 6.9 and 7.0, and bug #631 reopened.

i'll fix this.

removed from the distribution as we have no right to distribute this.  hopefully
we can get the licensing sorted for 7.1.