$NetBSD$

--- configure.in.orig	2006-02-25 21:27:07.000000000 +0000
+++ configure.in
@@ -31,6 +31,11 @@ if test "$automake" = "FAIL"; then
     AC_MSG_ERROR(Cannot continue: automake not found)
 fi
 
+AC_PATH_PROGS(expr, gexpr expr, FAIL)
+if test "$expr" = "FAIL"; then
+    AC_MSG_ERROR(Cannot continue: expr not found)
+fi
+
 dnl Checks for libraries.
 
 dnl Checks for header files.
