Digital BW, The Print

This is all with Epson brand K3 inks and Photoshop CS2 and no RIPs.
when I had the PK cartrige installed the ABW mode was greyed out (not 
available as an option). I have read in some posts that some folks have 
used the PK with matte papers like Epsons Enhanced Matte. Am I 
hallucinating or how does one trick the R2400 to print on Matte with 
the PK. 
I don't intend for this post to turn into a debate on whether or not 
one should or shouldn't or which is better on Matte. That has already 
been debated on other forums.

Thanks Eddie