[imp] Encoding Of Content-Disposition: attachment; filename

[admin@vilagkozepe.hu]

Hello!

My imp is "Mail (imp)  H3 (4.3.4)"
I've just upgraded from a really old Horde. New imp is Great. (I  
haven't migrates, my .confs are brand new.
I have a pythonfilter running that heals ever RFC-ignorant mail.

For example the attachment FILENAME field.

imp generates:
--------------------------------
Content-Disposition: attachment;
  filename*="utf-8''acc%C3%89nt.txt"
--------------------------------


my script corrects this as follows:
--------------------------------
Content-Disposition: attachment; filename="=?utf-8?q?acc=C3=89nt=2Etxt?="
--------------------------------

Is the First form correct? [I know I should look at RFC :) ]
Why was that changed in imp?

Thank You
-- 
Szépe Viktor
+36 20 4242498  viktor at indamail.hu
.
domain:   vilagkozepe.hu
IP:       91.82.52.238
physaddr: H-1143 Budapest, Ilka u. 31.
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