There is an FAA list of WWII era aircraft that are eligible for the Limited certificate. A-26 is eligble. The category was closed decades ago and no new types are eligible. The following table is from the FAA site regarding special airworthiness certificates.
http://www.faa.gov/certification/aircraft/
Category
Purpose(s)
14 CFR References
Primary Aircraft flown for pleasure and personal use 14 CFR section 21.24
14 CFR section 21.184
Restricted Aircraft with a "restricted" category type certificate, including:
Agricultural.
Forest and wildlife conservation.
Aerial surveying.
Patrolling (pipelines, power lines).
Weather control.
Aerial advertising.
Other operations specified by the Administrator.
14 CFR section 21.25
14 CFR section 21.185
Limited Aircraft with a "limited" category type certificate 14 CFR section 21.189
Provisional Aircraft with a "provisional" category type certificate for special operations 14 CFR part 21 subpart I
Special Flight Permit Special-purpose flight of an aircraft that is capable of safe flight 14 CFR section 21.197
Experimental Research and development.
Showing compliance with regulations.
Crew training.
Exhibition.
Air racing.
Market surveys.
Operating amateur-built aircraft.
Operating kit-built aircraft.
Operating light-sport aircraft.
14 CFR section 21.191
14 CFR section 21.193
14 CFR section 21.195
Multiple Multiple airworthiness certificates 14 CFR section 21.187
Light-Sport Operate a light-sport aircraft, other than a gyroplane 14 CFR section 21.190