Someone going by the handle Dr. Strange recently announced that he, with the help of a small team, was porting Akalabeth to the Commodore 64:

Happy to announce we are converting Akalabeth: World of Doom (aka Ultima 0) to the C64. We just started working on it, so updates will be posted here soon.

The team in question is evidently Atlantis64; you can find their Facebook page here. The port is being implemented using a mix of BASIC and MC in order to achieve higher-resolution graphics. Dr. Strange intends to produce a straightforward port; he admits to being something of a purist where Ultima is concerned.

A short video demonstrating an early build of the port has also been released:

As of May 5th, Dr. Strange has stated that the main part of the game has been almost entirely ported; the team are now testing it and fixing bugs as they emerge. You can follow this thread at the Lemon forums for updates.