+dnl --------------------------------------------------------------------
+dnl Check for version compatility with back-bdb
+AC_DEFUN([OL_BDB_COMPAT],
+[AC_CACHE_CHECK([Berkeley DB version for BDB backend], [ol_cv_bdb_compat],[
+ AC_EGREP_CPP(__db_version_compat,[
+#include <db.h>
+
+ /* this check could be improved */
+#ifndef DB_VERSION_MAJOR
+# define DB_VERSION_MAJOR 1
+#endif
+
+/* require 4.0 or later */
+#if DB_VERSION_MAJOR >= 4
+ __db_version_compat
+#endif
+ ], [ol_cv_bdb_compat=yes], [ol_cv_bdb_compat=no])])
+])
+