"convert" from ImageMagick fails

[Prof. Michael Stiber]

I'm trying to use htlatex, but it fails while trying to convert 
graphics.  The dvips performed on the .idv file produces a .ps file 
that views fine in ghostview, but the "convert" command fails. Here's 
the command line and the error:

convert -crop 0x0 -density 110x110 -transparent '#FFFFFF' zzsyllabus.ps 
syllabus4x.gif
src/gxccman.c:574: failed assertion `cc->pair == pair'
src/gxccman.c:574: failed assertion `cc->pair == pair'
convert: Postscript delegate failed.

Anyone familiar with the source code who knows why that assertion would 
fail? I've re-installed all of the software that I thought was relevant 
using i-Installer.

Mike Stiber