fix for tools/ps2png that must be submitted to the upstream maintainer
--- a/tools/ps2png
+++ b/tools/ps2png
@@ -2,7 +2,7 @@
 #ps2png script by Ian Hutchinson 1999; use at your own risk.
 #You need Ghostscript and the netpbm utilities installed. 
 if [ $# -lt 2 ] ; then
-       echo " Usage: ps2png <file.ps> <file.gif> [<icon.gif>]" 1>&2
+       echo " Usage: ps2png <file.ps> <file.png> [<icon.png>]" 1>&2
        exit 1
 else 
     echo "Calling ghostscript to convert, please wait ..." >&2
