I went through the tedious procedure for installing Apache2::Request by doing the whole thing in the source directory of libapreq2* and thought do post this with more details to help others in the similiar situation.
1. installing apache2-threaded-dev for getting "apxs2" binary installed. I also have to change the "apxs" binary name in "configure" script to "apxs2" to pass the configuration process.
2. installing apache2-mod-perl2-dev for problems encountered during the "make" process where mod_perl.h, modperl_perl_unembed.h and other header files are needed.
3. installing ExtUtils::XSBuilder::ParseSource is pretty staight forward and can be done in cpan environment without problem.
Thanks