private/rfc3464/1223.eml has "Will-Retry-Until" field

[azumakuniyuki]

Action: delayed
Status: 4.0.0
Diagnostic-Code: X-Unix; maildir delivery failed: error
    writing message: Disc quota exceeded
Will-Retry-Until: Wed, 16 Dec 2009 13:59:41 +0000 (GMT)

01118-8c26c46b6546587ce1ae084ba548e783.eml:Will-Retry-Until: Mon, 26 Mar 2001 03:42:45 +0100
01121-99c4e57563b223e14cc057530b81d7b4.eml:Will-Retry-Until: Mon, 2 Jul 2001 13:07:44 +0200
01123-a6dd655207dcffa633f79984e93cec5b.eml:Will-Retry-Until: Sun, 5 Aug 2001 02:02:05 +1200
01124-5ab1d5628918234860845a14a82d17f3.eml:Will-Retry-Until: Tue,  9 Oct 2001 10:20:46 +0200 (CEST)
01223-5332639ece1d0dd090cfc4fd6892375b.eml:Will-Retry-Until: Wed, 16 Dec 2009 13:59:41 +0000 (GMT)
01263-58a0504d846d6a83fcd395821182c657.eml:Will-Retry-Until: Sat, 19 Nov 2016 21:57:49 -0200 (BRST)
01273-3ee3f6376001f6373224573ac4325449.eml:Will-Retry-Until: Mon,  5 May 2008 05:51:07 +0300 (EEST)