Hey guys!
If you choose the 'more options' at the beginning of the install and type 'expert', you'll get the option to select which CD's you have available. CD4 is listed there by default, so you can deselect it and then you don't get prompted for it at all.
;-)
"A computer lets you make more mistakes faster than any other human invention in history...with the possible exception of handguns and tequila." -Mitch Ratcliffe