PNG -- can't we all just get along?

[Ross Boylan <RossBoylan@stanfordalumni.org>]

I have a mostly testing system.  When I try to get the latest
development stuff for libpng, this happens:
# apt-get -du install libpng12-dev
Reading Package Lists... Done
Building Dependency Tree... Done
The following packages will be REMOVED:
  imlib-dev kde-designer kdebase-dev kdelibs-dev libkmid-dev libkonq-dev libpng2-dev libqt-dev 
The following NEW packages will be installed:
  libpng12-dev 
0 packages upgraded, 1 newly installed, 8 to remove and 138  not upgraded.

libpng10-dev is installed on my system.

I thought from the Debian README that the two versions of png could
coexist, but it doesn't seem to work.  libpng10-dev and libpng12-dev
apparently can coexist, but libpng2-dev and dependents are getting the
boot.

Is there anything I can about this?  If not, it seems I have to choose
between being able to develop for gnome 1 vs kde (via qt), and can't
do both at the same time.