Pup (Printer Utility Program) is a GUI utility for maintaining your printer.  

Supports following printers
  * Lexmark Optra Color 40 
                  Color 45 
                  E310 
  * HP 2100M
       4000
       LJ4 Plus  

With read back additionally all PJL printers are supported.
see lptcontrol(8)

WWW: http://pup.sourceforge.net/