[pjsip] Python PSJUA.py - adding headers don't work

[Peuralahti Jari]

In the pjsua documentation http://www.pjsip.org/python/pjsua.htm#Buddy

is written that optional headers can be added using hdr_list:

send_pager(self, text, im_id=0, content_type='text/plain',
hdr_list=None)
    Send instant message to remote buddy.

    Keyword arguments:
    text         -- Instant message to be sent
    im_id        -- Optional instant message ID to identify this
                    instant message when delivery status callback
                    is called.
    content_type -- MIME type identifying the instant message
    hdr_list     -- Optional list of headers to be sent with the
                    request.

how ever I have not applied get to this work right.

This is what I have tryed
    header_list = []
    header_list.append("Subject=Test")
    header_list.append('Subject: Foo')
    header_list.append('Subject:, foo')
    ... some code



buddy.send_pager(input,content_type='text/plain',hdr_list=header_list)

and for result I get SIP MESSAGE with basic headers, but none
of my optional headers except four ":" empty lines:

MESSAGE sip:jari at mydomain.fi SIP/2.0.
Via: SIP/2.0/UDP
myip:5080;rport;branch=z9hG4bKPjRT8HRroNeYqMblLt8bxfSxI7rDfAUZR4.
Max-Forwards: 70.
From: <sip:jari at mydomain.fi>;tag=Rro.mo0pMTmkoiS8cAs74ELT4X.eve98.
To: <sip:jari at mydomain.fi>.
Call-ID: gA5YAVKuj-jRmVItXv.qE9VwM4dPpODt.
CSeq: 63465 MESSAGE.
Accept: text/plain, application/im-iscomposing+xml.
Contact: <sip:jari at myip.fi:5080>.
User-Agent: Jari's Python Script.
: .
: .
: .
: .
Route: <sip:sip.mydomain.fi;lr>.
Proxy-Authorization: Digest username="jari",
realm="mydomain.fi",
nonce="4b8e859d000005f04bf656f8fdd980b78d865ef27632a8e9",
uri="sip:jari at mydomain.fi",
response="a94938b0df8be6c407d95d93e5aa02d1",
cnonce="0u45VvJKoydngfonnRbaapVgvuIhr.00", qop=auth, nc=00000001.
Content-Type: text/plain.
Content-Length:    12.
.
TEST MESSAGE
-------------------------

What I am doing wrong or isit a bug?

Cheers,

Jari