encryption algorithm

Hi all.I have a question concerning this subject.There is a problem right now that many are experiencing with respect to connecting to ebay using firefox.The following message pops up:

"Firefox and srv.main.ebayrtm.com cannot communicate securely because they have no common encryption algorithms"

My question is what is the purpose and/or function of this algorithm?Does this mean passwords and info are exposed if this connection is not made?
When clicking on the alert message it disappears and then am able to access account but not sure if all is safe.If this has been addressed on this board please direct me to it.Thanks in advance.