--- configure.ac.old	2006-10-08 12:38:54.000000000 +0200
+++ configure.ac	2006-10-08 12:39:19.000000000 +0200
@@ -49,6 +49,8 @@
 EXULT_DATADIR="$datadir/exult"
 ARCH=""
 
+AC_PATH_XTRA
+
 # determine windowing system from 'host'
 AC_MSG_CHECKING("windowing system")
 case "$host_os" in