apt-get is not cpan :) use  cpan AnyEvent::MPRPC::Client

See A Guide To Installing Modules

Are you aware there are two different ways to tackle managing the Perl modules? You can use Ubuntu's package management, or you can install your own "local" Perl and use CPAN to dial the modules as you wish.

The easiest, and least effort, is to "apt-get install" the apropriate Ubuntu package for the Perl module you want. You can search on the packages.ubuntu.com site to see if there is a package for the module(s) you want. (And, as already mentioned, Ubuntu and apt-get aren't apropos of PerlMonks.) You CAN fire up the Ubuntu-installed Perl's cpan utility, but you can run into problems. Subsequent Ubuntu updates may rollback, step on, or cause incompatibilities with modules you've installed by hand. Anyway, if Ubuntu has a package for the module you want, just apt-get install that package and leave your system Perl "on track" with Ubuntu packages.

For total control, you can download a copy of perl and compile/install it somewhere on your system. Then you use cpan (the command line utility) to install and manage your modules. Then you invoke your "local" perl specifically when coding, leaving the system Perl in a state exactly as your system packages expect it to be.

The easiest, and least effort, is to "apt-get install" the apropriate Ubuntu package for the Perl module you want.

Gee, thats what the OP was trying to do, but apt-get doesn't pack all of CPAN, there doesn't seem to be a

libanyevent-mprpc-perl

and AnyEvent::MPRPC::Client is pure-perl

http://www.deepakg.com/prog/2009/01/cpan-modules-on-ubuntu-apt-get-vs-perl-mcpan/

sudo apt-get libanyevent-perl

sudo cpan AnyEvent::MPRPC::Client

I don't know what "apropos" means. "sudo perl -MCPAN -e 'install AnyEvent::MPRPC'" fixed my problem and installed it. Of course, now the problem is that it is missing basic functionality that the ruby version of MessagePack-RPC has (like Login, for instance). Sigh. Charles.