diff --git a/configure.in b/configure.in
index 126e32af1..30e798185 100644
--- a/configure.in
+++ b/configure.in
@@ -54,6 +54,18 @@ AM_CONDITIONAL(KRB4, test "$with_krb4")
 AC_SUBST(LIB_krb4)
 AC_SUBST(INCLUDE_krb4)
 
+AC_ARG_ENABLE(kaserver,
+[  --enable-kaserver	   if you want the KDC to try to emulate a kaserver],
+[
+if test "$enableval" != no; then
+	AC_DEFINE(KASERVER, 1)
+	if test "x$with_krb4" = "x"; then
+		AC_MSG_ERROR(kaserver requires krb4)
+		exit 1
+	fi
+fi
+])
+
 AC_TEST_PACKAGE(readline,readline.h,libreadline.a,-lreadline)
 
 AC_C_BIGENDIAN