I've never been able to install Apache2::Request via CPAN. It won't make; however, I did manage to get it installed by downloading libapreq2.
Then, I used the following for ./configure:
in reply to REST, CGI::Application::Plugin::Apache and Apache2::Request
Then I ran /sbin/ldconfig /usr/lib. To double-check, I ran pmpath on Apache2::Request, and it found it.
./configure --enable-shared --with-gnu-ld --enable-perl-glue --with-pe