PASTHRU not passed through for make install?

[Kurt D. Starsinic]

Hi,

    I was surprised today when I realized that PASTHRU isn't passed
through for a `make install', which means that the PREFIX set in my
top-level Makefile.PL isn't being applied recursively.  Bug or feature?
Any suggested workarounds (without editing the sub-Makefile.PL's)?

    - Kurt