Conny, the X-26 does not support midi sync, nor does any other analog multitracker currently on the market today. If you insist on analog, the Fostex 480 multitracker had an optional midi sync unit, sold separately, and You might be lucky and get your hands on a working unit.
However, I suggest you forget about analog recording, especially if you plan to do any midi stuff. This is the age of digital, really, and a lot of effort has gone into designing the operation of the units to be as 'analog-like' as possible. A lot of the digital HD recorders out there support midi sync, examples include the Fostex VF-16 and the Fostex MR-8, but the feature should be available in almost any HD recorder brand you could mention, like Yamaha, Zoom, Korg, or Tascam.
regards, Nils