If you are looking for a true XXL than the Coda may not fit. It's largest size is a 23" frame, also the Trek Multitracks. KHS and Breezer make a steel XXL that may fit but I have never ridden one but have been looking for a used one for a long time.
When Soma put the New Albion Privateer on sale last year I decided to build my own. Probably not the most economical way to go, I had a lot of parts already on hand. But at 6'6" this frame fits perfect.
Trek does make the FX series in XXL. How tall are you?