O navegador padrão do Android 2.2 pode ser atualizado (sem atualizar todo o sistema operacional)?
Infelizmente, não está disponível através do mercado do Android, tanto quanto eu sei.
Can android 2.2 default browser be upgraded (without upgrading the whole OS) ?
Unfortunately, it is not available through Android market as far as I know.
You cannot update inbuilt browser even though your phone is rooted. Anyway you have some other good alternative browsers in market like Dolphin, Opera.
I am not sure if the browser can be updated, even with root. The best thing is to root your device and install a better ROM, if you are stuck on an old Android version and unhappy with the browser.