$ cpan
cpan>look DateTime
[/path/to/the/cpan/Module-build-directory]# 

##</code><code>##

[/path/to/the/cpan/Module-build-directory]# exit
cpan> exit
$ cd /path/to/the/cpan/Module-build-directory
$ perl Makefile.PL 
$ make
$ make test        
$ make install