Some of them should not be needed at all:
libv8 - This is used by therubyracer as far as I know. The system libv8 is
used for therubyracer instead and if there is other need, it should be used
there as well.
This is unfortunately not true for new therubyracer versions. therubyracer now depends on
libv8 again and libv8 can either use its bundled version of v8 or the system one . So I
guess we will end up with rubygem-libv8 eventually.
Bohuslav "Slavek" Kabrda.