Changes since version 3.15:
・ Added set bundle max-logins num option at bundle level for limiting the max. amount of concurrent logins with the same username. Original idea submitted by Andrey V. Elsukov <bu7cher@land.ru>.
・ Mpd has now its own link-stats with 64 bit counters. This is a workaround for the 32 bit limitation of ng_ppp_link_stat.
・ RADIUS enhancements:
□Set the RAD_ACCT_INPUT_GIGAWORDS and RAD_ACCT_OUTPUT_GIGAWORDS attributes when sending accounting requests.
□ Use the RAD_ACCT_INTERIM_INTERVAL attribute.
・ Implemented PPPoE server functionality
・ Added ability to configure ipfw firewall for clients using vendor specific RADIUS attributes. Submitted by Alexander Motin <mav@alkar.net>.
・ Added the possibility of choosing link by it's number (same as RAD_NAS_PORT) instead of name

別にBフレッツ接続のためにPPPoEをmpdでしている分には関係なさそう。
multilink patchは当たっているのかな?