Anyone ever have one ?

Mine might be, on the rear brake pump.

I notice a few drops every now and then right below where the
brake cylinder is (near the heel of my ight foot)

Anyone know if this is a common problem or what ?

I'm running a 1999 FXSTC Softail.

I don't know about it being a common problem, but I had a buddy who had the same problem. Is the brake getting squishy or have you noticed anything different with it?

The brake is working fine, I'm just thinking that is might be
a seal or loose connection.
Which may cause the leak.

Yeah, I'd just check all the lines first, hopefully (i guess) it's something small in one of them.

If I were you I would get it figured out and fixed before I rode. Brakes and tires are your life. Also, brake fluid is very damaging to paint. If I were to guess I think it is probably a seal in the cylinder. Good luck. Lets us know what the fix is. Take Care and Ride Safe.