in reply to LWP::UserAgent @ Ubuntu 8.04 64-Bit
A word of warning, if I where you I'd leave the system perl alone and build your own. Simply download and unpack the source (http://www.perl.org/get.html) and configure it like so:
./Configure -des -Dprefix=$HOME/perl make test make install
Ubuntu uses the the version of perl which ships with the system for some system tasks. IMHO it's best left alone.
Also you can use the method above to install various builds of perl on your system, should that interest you.