xlibmesa-gl-dev install bug ?

[Gaël Varoquaux <gael.varoquaux@ens.fr>]

  Hi,

    Installing the xlibmesa-gl-dev package from unstable I get a error
message :

oot@omega / $ apt-get -t unstable -f install
Reading Package Lists... Done
Building Dependency Tree... Done
Correcting dependencies... Done
The following extra packages will be installed:
  xlibmesa-gl-dev 
  The following NEW packages will be installed:
xlibmesa-gl-dev 
0 packages upgraded, 1 newly installed, 0 to remove and 784  not
upgraded.
7 packages not fully installed or removed.
Need to get 666kB of archives. After unpacking 3453kB will be used.
Do you want to continue? [Y/n] 
Get:1 http://ftp.us.debian.org sid/main xlibmesa-gl-dev 4.3.0-7   [666kB]
Fetched 666kB in 3s (215kB/s)           
(Reading database ... 134881 files and directories currently
installed.)
Unpacking xlibmesa-gl-dev (from .../xlibmesa-gl-dev_4.3.0-7_i386.deb) ...
dpkg: error processing
/var/cache/apt/archives/xlibmesa-gl-dev_4.3.0-7_i386.deb (--unpack):
 unable to create `./usr/X11R6/lib/libGL.a': No such file or
 directory
 dpkg-deb: subprocess paste killed by signal (Broken pipe)
 Errors were encountered while processing:
/var/cache/apt/archives/xlibmesa-gl-dev_4.3.0-7_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
      

      
  /usr/X11R6/lib does exist (as I have symlinked /usr/X11 to
/usr/X11R6), eventhough I don't think it is the "debian" way (if I am
not wrong debian puts X in /usr/X11).

  Anyway, this package currently does not install and it has frozen my
installation process on my computers.

   Thanks for all your work,

		     Gaël