Sharethis module shares link on social sites successfully but the link redirects to 'page not found'

Hi,
I am an intermediate drupal 7 user. I am within a bit of troubled water with my site now.
I have used sharethis module for my custom content type. Its working perfect. But my site is being hosted in a demo server for the time being. My site resides now in a folder within that domain and the path is similar to "mydemoserver.com/folderconsistingmysite". Whenever i share any content in social sites like FB, the link from the social site when clicked redirects to the destination site's 'page not found' page. I inspected the url and got that the url is wrong. Its printing the url like this "mydemoserver.com/folderconsistingmysite/folderconsistingmysite/content/node" . That repeated folder name in between the url is causing all the nuisance. This should have been "mydemoserver.com/folderconsistingmysite/content/node". Is there anything to be done with the $base_url?? i tried declaring it locally by removing the 'global ' keyword and defining it to be only 'http://www.mydemoserver.com' without trailing slash. But of no use. Rather my sites's images got blank after doing this. I just rolled back to default. Is this scenario gonna change once my site goes live?? I read in a thread in www.stackoverflow.com that if the site doesnot reside into root of the domain, then such wrong url might occur. What am i supposed to do now? Any help or support is highly appreciated.