diff --git a/docs/cmu-user/Makefile b/docs/cmu-user/Makefile
index 15ae1ad44709c73b4426bfd1e05240c26f8ccbc1..5cc85238eabc1c61462a08fb5e4fb616fde99470 100644
--- a/docs/cmu-user/Makefile
+++ b/docs/cmu-user/Makefile
@@ -83,7 +83,7 @@ all: cmu-user.ps
 # convert the Postscript file to duplex (will print double-sided if
 # the printer supports it)
 %.ps : %.ps1
-	psset -d -o $@ $<
+	if [ -x psset ]; then psset -d -o $@ $<; else cp $< $@; fi
 
 # Tar up the html files
 cmu-user-html.tgz : cmu-user.html