+
+#ifdef HAVE_DB_H
+#include <db.h>
+#elif defined(HAVE_DB4_DB_H)
+#include <db4/db.h>
+#else
+#error Neither <db.h> nor <db4/db.h> was found by configure. Install db4-devel.
+#endif
+
+
+#if DB_VERSION_MAJOR < 4 || DB_VERSION_MINOR < 1
+#error Citadel requires Berkeley DB v4.1 or newer. Please upgrade.
+#endif
+