On Linux mediaType from mess. body iprepended to ContentType

On linux machine the media type is prepended from message body to the Header ContentType. Where the same does not happen on Windows machine.
Due to this all our test cases are failing on linux environment. Can some one please help us to resolve this problem asap?

Hers is the scenario:

I am executing a HTTP Post request. In my request I have added two Header attributes i.e. Content-Type and MIME_version
and also I am also passing some value to request via message body.

On execution I see the following Content-Type value being sent in the request. The "application/xml" is prepended to Content-Type from message body


Note: Please see the Content-Type value


Request from On Linux:
----------------- Properties ------------------------------
StatusCode: 200
Encoding:
Method: POST
Username:
HTTP Version: HTTP/1.1
Endpoint: https://SXXX.yahoo.com/rest/v1/d94
URL: https://SXXX.yahoo.com/rest/v1/d94

---------------- Request ---------------------------
MIME-Version: [1.0]
Host: [sxxx.yahoo.com]
Content-Length: [790]
Accept-Encoding: [gzip,deflate]
User-Agent: [Jakarta Commons-HttpClient/3.1]
Content-Type: [application/xml, multipart/form-data; boundary=----------Ij5Idjahdjhasjkdhasnjkdaskjd]



In case of windows I don't see any media type value being prepended to Content-Type

Request from windows:
POST https://Sxxx.yahoo.com/rest/v1/d94 HTTP/1.1
Accept-Encoding: gzip,deflate
MIME-Version: 1.0
Content-Type: multipart/form-data; boundary=----------Ij5Idjahdjhasjkdhasnjkdaskjd
User-Agent: Jakarta Commons-HttpClient/3.1
Host: sxxx.yahoo.com
Content-Length: 790

Can you please help me to resolve this issue?

Thanks


SoapuI Version: 3.6.1 (Release build)
Btw, I did try the same on 4.0 too and that did not help either