--- a/run-calibrate.sh.org	2006-10-12 10:19:42.000000000 +0000
+++ b/run-calibrate.sh	2007-02-09 17:54:55.000000000 +0000
@@ -1,3 +1,5 @@
 #! /bin/sh
 
-exec xtscal
+if [ -e /dev/input/touchscreen0 ]; then
+    exec xtscal
+fi