Can you provide exact steps to reproduce and example URLs ? I tried with a local wiki which uses SSL and couldn't even register a new target Wiki.

A similar bug (about this extension being broken) was logged in Debian:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=616011

I am having a similar problem.  I'm using LO 3.3.2, and when I use the Send to MediaWiki option, everything behaves as it should, but when my web browser appears, my wiki article has no text at all.  
I see the following in my console:  It looks as if the xsl filter is  not producing anything, because ".../3/user/temp/" does not exist.  I tried creating it manually and setting the permissions to 777, but that didn't seem to help at all.

11-04-12 3:43:50 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:43:50 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:43:50 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:43:50 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:43:50 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:43:50 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:43:54 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:43:54 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:43:54 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:43:55 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:43:55 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:43:55 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:43:55 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:43:55 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:43:55 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:43:55 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:43:55 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:43:55 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:43:56 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:43:56 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:43:56 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:43:56 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:43:56 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:43:56 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:44:04 PM	[0x0-0x237237].org.libreoffice.script[15432]	java.io.FileNotFoundException: /Users/myUser/Library/Application%20Support/LibreOffice/3/user/temp/svgb7.tmp/svgd6.tmp (No such file or directory)
11-04-12 3:44:04 PM	[0x0-0x237237].org.libreoffice.script[15432]		at java.io.FileInputStream.open(Native Method)
11-04-12 3:44:04 PM	[0x0-0x237237].org.libreoffice.script[15432]		at java.io.FileInputStream.<init>(FileInputStream.java:106)
11-04-12 3:44:04 PM	[0x0-0x237237].org.libreoffice.script[15432]		at com.sun.star.wiki.Helper.EachLine(Unknown Source)
11-04-12 3:44:04 PM	[0x0-0x237237].org.libreoffice.script[15432]		at com.sun.star.wiki.WikiEditorImpl.SendArticleImpl(Unknown Source)
11-04-12 3:44:04 PM	[0x0-0x237237].org.libreoffice.script[15432]		at com.sun.star.wiki.WikiPropDialog$1.run(Unknown Source)
11-04-12 3:44:04 PM	[0x0-0x237237].org.libreoffice.script[15432]	Apr 12, 2011 3:44:04 PM org.apache.commons.httpclient.HttpMethodBase getResponseBody
11-04-12 3:44:04 PM	[0x0-0x237237].org.libreoffice.script[15432]	WARNING: Going to buffer response body of large or unknown size. Using getResponseBodyAsStream instead is recommended.
11-04-12 3:44:05 PM	[0x0-0x237237].org.libreoffice.script[15432]	nSubmitCode = 302

I should mention I am using Mac OSX 10.6.7 with java 1.6.0_24

NOT reproducible with "LibreOffice 3.3.2  – WIN7  Home Premium  (64bit) German UI [OOO330m19 (Build:202 / tag 3.3.2.2)]". I was able to create Wikipedia article <http://de.wikipedia.org/wiki/Nmaampor> without any problems, and it looked fine. Mac specific?

@sianariman
"Can't create" sounds like user unability, but I believe you wanted to report a LibO problem? ;-)

Hints on <http://wiki.documentfoundation.org/BugReport>might help you to create a much more useful report.

Please:
- Attach a sample document 
- Attach screenshots with comments (you can add information using LibO DRAW
  and then attach your screenshot with comments as PDF) if necessary
- Contribute a step by step instruction containing every key press and every 
  mouse click how to reproduce your problem (additionally: Wiki account data)
- add information 
  -- what exactly is unexpected
  -- and why do you believe it's unexpected
  -- concerning your PC 
  -- concerning your LibO localization (UI language)
  –- Libo settings that might be related to your problems 
  -- how you launch LibO
  -- everything else crossing your mind after you read a.m. URL

[This is an automated message.]
This bug was filed before the changes to Bugzilla on 2011-10-16. Thus it
started right out as NEW without ever being explicitly confirmed. The bug is
changed to state NEEDINFO for this reason. To move this bug from NEEDINFO back
to NEW please check if the bug still persists with the 3.5.0 beta1 or beta2 prereleases.
Details on how to test the 3.5.0 beta1 can be found at:
http://wiki.documentfoundation.org/QA/BugHunting_Session_3.5.0.-1

more detail on this bulk operation: http://nabble.documentfoundation.org/RFC-Operation-Spamzilla-tp3607474p3607474.html

needinfo keyword redundant by needinfo status.

Dear bug submitter!

Due to the fact, that there are a lot of NEEDINFO bugs with no answer within the last six months, we close all of these bugs.

To keep this message short, more infos are available @ https://wiki.documentfoundation.org/QA/NeedinfoClosure#Statement

Thanks for understanding and hopefully updating your bug, so that everything is prepared for developers to fix your problem.

Yours!

Florian