Python's email module - problem with umlauts in some email clients

[Nico Grubert]

Hi there,

I wrote a short python script that sends an email using python's email
module and I am using Python 2.3.5.
The problem is, that umlauts are not displayed properly in some email
clients:

+ On a windows machine running thunderbird 1.0.2 umlauts are displayed
properly.
The email header contains "Content-type: text/plain; charset=utf-8"
so the email client's character encoding automatically switches to
"Unicode (UTF-8)"

+ On a solaris machine running thunderbird 1.5.0.8 and on a macintosh
machine running eudora umlauts are *not* displayed properly.
The email header does not contain any "Content-type". If I manually
switch the email client's character encoding to "Unicode (UTF-8)", the
umlauts are displayed properly. Therefore, I guess it has something to
do with the missing "Content-type: text/plain; charset=utf-8"
information in the email header.

Any idea why the "Content-type: text/plain; charset=utf-8" is missing?
Here is my script:

#------------------------------------------------------------------
# send email
from email.Header import Header
import email.Message
import email.Utils
import mimetypes
from smtplib import SMTP

host = 'mail.example.com'
mFrom = 'a*********@example.com'
mTo = 'f******@example.com'
mSubj = u'f\xfcr'
mBody = u'f\xfcr foo bar'
mBody = mBody.encode('UTF-8')

mainMsg = email.Message.Message()

mainMsg['From'] = mFrom
mainMsg['To'] = mTo
mainMsg['Subject'] = mSubj
mainMsg.set_payload(mBody)

mainMsg['Date'] = email.Utils.formatdate(localtime=1)
mainMsg['Message-ID'] = email.Utils.make_msgid()
mainMsg['Mime-version'] = '1.0'
mainMsg['Content-type'] = 'text/plain; charset=utf-8'
mainMsg['Content-transfer-encoding'] = '8bit'
# 'quoted-printable' does not work either
# mainMsg['Content-Transfer-Encoding'] = 'quoted-printable'

s = SMTP(host)
s.sendmail(mFrom, [mTo], mainMsg.as_string())
s.close()
#------------------------------------------------------------------

Regards,
Nico