Foreman » Installer

I am unable to install the foreman-install on debian squeeze 6.0.6.
ruby-highline does not exist in the package list. It seems the package name is wrong:

puppetmaster ~ » sudo apt-get install foreman-installer
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
foreman-installer : Depends: ruby-highline but it is not installable
E: Broken packages

puppetmaster ~ » apt-cache search highline
libhighline-ruby-doc - High-level interactive IO Ruby library (documentation)
libhighline-ruby1.8 - High-level interactive IO Ruby 1.8 library
libhighline-ruby1.9.1 - High-level interactive IO Ruby 1.9.1 library
libhighline-ruby - High-level interactive IO Ruby library (default Ruby version)