diff --git a/configure.ac b/configure.ac
index 2d84162f..ec82b835 100644
--- a/configure.ac
+++ b/configure.ac
@@ -32,7 +32,9 @@ PKG_CHECK_MODULES([GMODULE], [gmodule-2.0])
 AC_SUBST(GMODULE_CFLAGS)
 AC_SUBST(GMODULE_LIBS)
 
-AM_PROG_LEX	
+AC_PATH_PROG([FLEX], [flex])
+test "$FLEX" || AC_MSG_ERROR([flex not found])
+
 AC_PROG_LIBTOOL
 LIBTOOL="$LIBTOOL --silent"
 AC_PROG_INSTALL