Collation problems

[Justin Hendrickson]

I have a HP LaserJet 4100 MFP installed, using this PPD file: http://www.linuxprinting.org/foomatic-db/db/source/PPD/HP/mono_laser/HP_LaserJet_4100_MFP.ppd

I'm using the following command:
lpr -P printer -# 3 -o Collate=True < README

README is a two page document.

Instead of getting three collated copies, I get one copy. If I remove the -o Collate=True, I get three uncollated copies.

Is there something I'm doing wrong here? What do I need to do to get this working?