If you just want plain v4 firmware (without the region free DVD mod) you can ask Toshiba themselves to send you a disc. Alternatively, hook up the player via Ethernet to get it onto the Internet and update it that way.

The avforums links however also include details on doing the region free DVD mod. These should let you upgrade to v4 firmware once the mod has been done. That's what I did with the EP35, though it was an easier process with the EP35.

I was acutally looking for the 4.0 firmware for this player, but on the http://www.toshibahddvd.co.uk/supportpage_uk.html page, I can only see the documents/manuals