The URL bar autocomplete feature is not working correctly, does anyone else have this problem?

I was running version 9.x and had this problem, so I have just updated to Firefox 11 but this is not helping. The issue is that the URL bar will not let me type a new address in some cases - prefering instead to refer me to a previously visited address. Perhaps it would be better if I gave an example: I am trying to go to a site I haven't visited before, e.g. holden.com.au I type 'h', and the URL bar suggests that I go to my Hotmail login page (the URL for this starts with 's'), and autofills the rest of the far (so now I am in the situation where I have an address in the bar starting with 's'). This means I can't continue entering the intended address. Can this be fixed, or is it just an issue for me?