[i18n] Mail header related patch.

[UEMURA (fka. MAENAKA) Tetsuya]

Hi all.

First off, thank everyone at Horde for this excellent software.

Attached is a patch against for framework of cvs heads, as of Apr. 8. By
applying this makes IMP

a) encodes field-body of header which contains non-ASCII or ASCII
control codes into BASE64. Especially for Subject field, non-ASCII
characters (but which consists of ASCII codes) are often used, and
without this patch, even if the message sent by IMP to IMP, contents
never appear correctly, because used characters are within the range of
ASCII from 00h to 7fh, and the receiver-side IMP can't know what
charsets used. FYI, ISO-2022-JP is one of these charsets.

b) can handle correctly " quoted comment of e-mail addresses. Without
patch, for example, when replying to the message which has
From: "Foo At Bar" <foo at bar.com>
header, re-quoted string
"\"Foo At Bar\"" <foo at bar.com>
appears in To field of compose window. Same happens when forwarding.
The patch fix them.

Please someone review and if useful, commit it into tree.

Regards.

--
UEMURA (fka. MAENAKA) Tetsuya
maenaka at pluto.dti.ne.jp