* (mailbox/filter_trans.c, as of 2004-11-28). Improved by review
* from Paul Eggert, Bruno Haible, and Stepan Kasal.
*
- * See also RFC 3548 <http://www.ietf.org/rfc/rfc3548.txt>.
+ * See also RFC 4648 <http://www.ietf.org/rfc/rfc4648.txt>.
*
* Be careful with error checking. Here is how you would typically
* use these functions: