installcheck vs regression DLLs

Hi!

When running "make installcheck", the DLL files for the regression tests
are loaded from the source tree "../../../contrib/" etc. While this
certainly makes a bit sense, it poses a problem for binary
distributions that want to run the regression tests. It also causes a
small problem for the msvc build in that the DLL files are built into a
$(top)/Debug/<dllname>/<dllname>.dll and thus needs to manually be
copied there.

Would it make sense to have a standard way to run the regression tests
against DLL files on the *installed* system? Perhaps even have
installcheck do so? Meaning it would load the DLLs or .so's from $libdir
instead of the source tree?

If not, other suggestions on how to solve it?

//Magnus