Google Firefox requests failing

If you are receiving messages such as:

"We're receiving automated connection requests generated by a virus or spyware, and it seems your computer or network were infected"

And it happens only if you click the search-bar, if you call http://google.com, insert your query and everything runs smoothly...

Click the search bar, select "Manage search engine list", click Google, edit "keyword" and insert:

http://www.google.com/search?q=

Click twice on OK. That should be enough to do the trick