Digital BW, The Print

Hi,

I am trying to use the MIS variable tone inks in the prefilled 
cartridges on an epson 1280, photoshop6, windows2000.

I have used the purge jpgs and printed a set of pages and the colors 
other than black look perfect.  

With regard to black -- I just printed 3 pages using the black purge 
jpg file.  They look identical, solid black for 1/4 inch followed by 
the rest of the page looking like dark grey with a set of black 
strips (about 80 of them).  I just printed the 21step greyscale strip 
image from the site and got that banding and grey at 100%, and the 
banding persists till 85%.  

Suggestions would be appreciated, I dont know what to do next.

Thanks,
Mark
http://www.interwalk.com/pinhole.htm