I have set up a printer (HP laserjet 1100) for apsfilter version
7.2.2. It prints, but the top 0.5" (or so) of each page is missing. So
it looks like the margins are misaligned (there is enough physical
margin space in each sheet). How do I align the margins? 

I am using letter paper, the printcap line is:
laserjet|PSgs;r=600x600;q=draft;c=gray;p=letter;m=auto:\

And I have added the following line to the printer's apsfilterrc file:
GS_FEATURES='-sDEVICE=laserjet'

Basically, I'm looking for some postscript or gs magic that will move
the printed stuff "down" by a bit. But to qualify, the solution must
incorporate that into apsfilter's system in some way which will work
for multiple-page jobs, and will not require me, after setting it up,
to do anything manual after submitting the print job.