On Fri, 4 Jan 2008, John C Klensin wrote: > > However, there is also a rule that, if no MX records are present at a > particular node, the mail system looks for an A RR at the same node and > treats it as if its label appeared with an MX preference of 0. That > default does not apply to AAAA records, so it is necessary that > operators understand that, if mail systems are to be accessed using > IPv6, they MUST have MX records at the relevant nodes. The only document that I know of which specifies IPv6 email routing is RFC 3974, which says that AAAA should be treated exactly the same as A. As far as I know, Exim, Postfix, and Sendmail follow RFC 3974. Tony. -- f.a.n.finch <dot@xxxxxxxx> http://dotat.at/ IRISH SEA SHANNON ROCKALL MALIN: MAINLY SOUTHWESTERLY, BECOMING CYCLONIC FOR A TIME IN SHANNON, ROCKALL AND MALIN, 6 TO GALE 8, OCCASIONALLY SEVERE GALE 9, PERHAPS STORM 10 LATER IN SHANNON, ROCKALL AND MALIN. ROUGH OR VERY ROUGH, OCCASIONALLY HIGH. RAIN OR SQUALLY SHOWERS. MODERATE. _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf