Digital BW, The Print

Hello All,
      I run MIS VM through a Media Street Niagra CIS on my Epson 
1280.   Today I planned to return to printing after I had been out of 
town for a week and a half.   I ran a nozzle check and found that 
the black was not firing at all.   I fiddled around a bit, and now 
nothing comes out of any of the nozzles.   I did take the catrridges 
out, but I do have plugs and it doesn't appear as though there 
are any bubbles in the lines.  I even went as far as to recharge 
the vacuum in the black cartridge, but still nothing comes out.   
Cleaning cycles... purge patterns... nothing seems to help.   Any 
suggestions would be greatly appreciated.
Thanks in advance,
Justin Smith