Can't remove e-mail address from keyserver

I have an address in my PGP key which shouldn't be there. The key's on keyserver.pgp.com. I can't get the bad address out of my key; if I delete the key from within my PGP Desktop and then choose "synchronise," the bad address reappears. If I delete the key from my PGP Desktop and then exit it, I'm asked whether I want the changes uploaded, to which I respond "yes," ... but the next time I open PGP Desktop, it's still there! (And right now, I can't get through the Captcha on the keyserver's web page to check it online; I obviously enter the correct text, but am told it's wrong ... regardless of which browser (Firefox, Chrome, IE9) I use.) Any thoughts?