Could not find dependency .. Prereq for Archive::Download

[frippe75]

Get this error using the example in the readme:
archive { 'apache-tomcat-6.0.26':
ensure => present,
url => 'http://archive.apache.org/dist/tomcat/tomcat-6/v6.0.26/bin/apache-tomcat-6.0.26.tar.gz',
target => '/opt',
}

Error: Failed to apply catalog: Could not find dependency Class[Archive::Prerequisites] for Archive::Download[apache-tomcat-6.0.26.tar.gz] at /etc/puppet/modules/archive/manifests/init.pp:78