Other Hebrew Localization Options for Firefox
There are several other unofficial add-ons that can offer better Hebrew localization for your browser.
First, you can download a simple Hebrew calendar add-on that will add the Hebrew date to your browser toolbar. You can find the download here.
Second, you might find it useful to just have a translation add-on for your Firefox browser. Babelfish offers a simple add-on, but my loyalties personally go toward gTranslate. This is the add-on version of the Google translate interface. It's obviously quite versatile and is great for all translation needs, but offers suitable Hebrew translation. Note, that it is a computer trying to translate language, so it will be far from perfect. It can be downloaded through this link.
Third, you can also get a tool for quickly changing your keyboard layout for use in the browser. AnyKey offers a number of layouts, including Hebrew, which allows you to type in the Hebrew language. You can find the download link here, although it may not be fully compatible with Firefox 3.6.
These tools and add-ons should be fairly helpful if you want to further localize your Firefox browser for the Hebrew language.