-// Calculate with the prime number (for code generation)
-define('_ADD', (_PRIME * _PRIME / (pi() * $CONFIG['code_length'] + 1)));
+// Calculate "entropy" with the prime number (for code generation)
+define('_ADD', (_PRIME * _PRIME / (pi() * $_CONFIG['code_length'] + 1)));
+
+// Random number for e.g. "cache-buster" used in OpenX script
+define('CACHE_BUSTER', mt_rand(1000000, 9999999));
+
+// Extra title is empty by default
+$EXTRA_TITLE = "";