Eclipse GWT plugin Installation issue

I have been encountering a problem installing GWT eclipse plugin using the update site :

http://dl.google.com/eclipse/plugin/3.6

using this update url seems to raise an error:

Unable to Read repository at http://dl.google.com/eclipse/plugin/3.6/content.xml.
Connection reset

A workaround that works for me is to replace gwt eclipse update site with:

https://dl-ssl.google.com/eclipse/plugin/3.6