Sorry tushantin, but from what you are telling me I'm stumped. Seems like your Bamboo One's pressure should be working.
You've installed input-wacom-0.11.1 and don't see any errors during the compile. You shouldn't need to update Oneiric's default xf86-input-wacom-0.11.0 since your tablet should work with it. No scripts or anything to interfere.
Since your xinput list and list-props look OK let's check your Xorg.0.log. That is in /var/log. It usually is a big file so you might want to compress it before attaching it.