Here is another clinical trial being done by the NIH for people who don't yet have a diagnosis or a "possible" MS diagnosis. I am participating in this one.
http://clinicaltrials.gov/ct2/show/NCT00001156?term=multiple+sclerosis&rank=46
Its a great resource. I also recently found a site that matches patients to trials, http://trialx.org. i found it useful and have emailed an investigator through the site