We once thought that only Windows Mobile 6.5 devices could benefit from the new Pocket Internet Explorer, but Microsoft just said that some Windows Mobile 6.1 devices could also feature it, under some conditions. First, the device mush have 128MB of RAM and a 400Mhz+ CPU . Secondly, it is up to the handset maker to make this feature available. You will not be able to download a .cab file to install it as an normal application.

via pocketnow