Well, I did reboot even before wroting here. So let's make this clear, did You all use this file from Mediawire link, and it did install fine?
Edit - strange, I downloaded this file again into Mac, transfered into E51, extracted rar with x-plore and tried install, but same error occurred. Then I extracted rar in Mac and transfered sis file into E51, and voilaa, it installed like charm.
Bookmarks