请问如何发送utf8电子邮件？

import sys
import smtplib
import email
import re

from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

def sendmail(firm, fromEmail, to, template, subject, date):
    with open(template, encoding="utf-8") as template_file:
        message = template_file.read()

    message = re.sub(r"{{\s*firm\s*}}", firm, message)
    message = re.sub(r"{{\s*date\s*}}", date, message)
    message = re.sub(r"{{\s*from\s*}}", fromEmail, message)
    message = re.sub(r"{{\s*to\s*}}", to, message)
    message = re.sub(r"{{\s*subject\s*}}", subject, message)

    msg = MIMEMultipart("alternative")
    msg.set_charset("utf-8")

    msg["Subject"] = subject
    msg["From"] = fromEmail
    msg["To"] = to

    #Read from template
    html = message[message.find("html:") + len("html:"):message.find("text:")].strip()
    text = message[message.find("text:") + len("text:"):].strip()

    part1 = MIMEText(html, "html")
    part2 = MIMEText(text, "plain")

    msg.attach(part1)    
    msg.attach(part2)

    try:
        server = smtplib.SMTP("10.0.0.5")
        server.sendmail(fromEmail, [to], msg.as_string())
        return 0
    except Exception as ex:
        #log error
        #return -1
        #debug
        raise ex
    finally:
        server.quit()

if __name__ == "__main__":
    #debug
    sys.argv.append("Moje")
    sys.argv.append("newsletter@example.cz")
    sys.argv.append("subscriber@example.com")
    sys.argv.append("may2011.template")
    sys.argv.append("This is subject")
    sys.argv.append("This is date")


    if len(sys.argv) != 7:
        exit(-2)

    firm = sys.argv[1]
    fromEmail = sys.argv[2]
    to = sys.argv[3]
    template = sys.argv[4]
    subject = sys.argv[5]
    date = sys.argv[6]

    exit(sendmail(firm, fromEmail, to, template, subject, date))

输出量

> Traceback (most recent call last):   
> File "C:\Documents and Settings\Administrator\Plocha\Newsletter-build-desktop\sendmail.py",
> line 69, in <module>
>     exit(sendmail(firm, fromEmail, to, template, subject, date))   
>
> File "C:\Documents and Settings\Administrator\Plocha\Newsletter-build-desktop\sendmail.py",
> line 45, in sendmail
>     raise ex
>
>   File "C:\Documents and Settings\Administrator\Plocha\Newsletter-build-desktop\sendmail.py",
> line 39, in sendmail
>     server.sendmail(fromEmail, [to], msg.as_string())
>
> File "C:\Python32\lib\smtplib.py",
> line 716, in sendmail
>     msg = _fix_eols(msg).encode('ascii') UnicodeEncodeError: 'ascii' codec
>
> can't encode character '\u011b' in
> position 385: ordinal not in
> range(128)