Generating HP RTL

Hi GRASS gurus's

I need to print out a image into a NOVAJET II that
work with the HP RTL format and PostScript format.
Unfortunately I don't have a cartdrige to .ps format.

My question:

        How can I convert a .ps (or .tiff) to HP RTL format?

ThanX in advance, miltinho

P.S.: Please, if you have anyone suggestion let me know
        because it's URGENT!!

Milton@nimbus.dpi.inpe.br