Version 1.3.4 is available upstream. Please consider updating! It seems that version 1.3.4 is available upstream, while the latest version in the Gentoo tree is 1.3.1. You think this warning is false? Read more about it here.
GtkLP is an graphical frontend for CUPS, the Common UNIX Printing System.
It is used to have an easy (and graphical) access to all of the many options
of cups-managed printers. Package also includes GtkLPQ - a graphical
frontend for CUPS-Printqueues.