Using different versions of same package?

[Tilo Stritzky <t.stritzky@teles.de>]

Hi,

Is there a straightforward way to keep different versions of a certain
package?
The problem:
I installed OpenBsd 2.8 and added ghostview-1.5. this required (among others)
libpng-1.0.8.
After upgrading to 3.0 I installed xv. Now the required libpng is
1.0.12. 
When I try to add this it complains (rightly) that there is already a
libpng, and after removing this one the (older) ghostview wont work
anymore.
Eventually I threw out the old libpng, added it again with the `-R' flag
(don not register package) and then added the new libpng. This works but
is too much hassle and leaves me with an unregisterd package install.
Any sugestions?

thanks

tilo