Plotting with Print Manager

I've started to add PC's to my existing network of unix machines, and the plotting function leaves a lot to be desired compared with ME-10 unix. The particular problem I have is that we use expanded margins for our D & E size paper, and Print Manager doesn't like them, returning the message that the drawing exceeds paper size. I get this message even after adding custom sizes to the plotter dialog. It's as though there are hard coded limits built-in that can't be over-ridden. Does anyone know of a fix for this?