I would not mention anything in a cover letter that could give someone doubts about hiring you, let alone making a phone call to you. I wouldn't put anything on your resume that speaks to your religious background, "fringe" groups, any disibilities, etc. You are, as someone said, one of many, many resumes they recieve. The ONLY thing to include are those things generally considered attributes.

I would forget about the ADA, state laws against discrimination, whatever. The reality is- people discriminate all day long and twice on Sunday. Get in the door, any way that you can.

Edited to add- if it is the phone call itself that is difficult, tell people you are currently working/volunteering during the day and you need to be contacted through email...and make sure you have a professionoal email address. For instance, I would stay away from yahoo, hotmail, gmail, and the like. IMO- those addresses aren't as professional sounding as your local cable company, or phone company address. This is MY opinion, and my opinion only.