Relocatable @INC puzzle

[Paul Makepeace]

I might be misunderstanding the purpose of this...

I just built perl 5.12.1 with relocatable @INC but when I relocate (mv
~/perl5 ~/perl) the site_perl directories haven't moved, so CPAN
breaks.

  Compiled at Jul 12 2010 23:52:59
  @INC:
    /Users/paulmakepeace/perl5/lib/site_perl/5.12.1/darwin-thread-multi-2level
    /Users/paulmakepeace/perl5/lib/site_perl/5.12.1
    /Users/paulmakepeace/perl/lib/5.12.1/darwin-thread-multi-2level
    /Users/paulmakepeace/perl/lib/5.12.1

Rationale: I'm hoping to be able to build a perl that's completely
self-contained that I can then bundle as part of an app/git checkout.
The various developers will all be working with this on in their own
home directories so this perl needs an @INC that's entirely relative.

I can sort of see that there's an argument that moving the perl
shouldn't move the CPAN but wondering if there's an official line, or
this is a bug, or currently under discussion, and what the preferred
way to solve this is (local::lib?), ...

Paul