Logging onto secure sites

[sirgeorge]

Why does my Mac give me this error message and how can I fix it? - "Safari can’t open the page “https://signin.ebay.com/ws/eBayISAPI.dll?SignIn&Using…ssPageName%3DH%253AH%253AMYEBAY%253AUS&pageType=1883” because it couldn’t establish a secure connection to the server “signin.ebay.com”. "

How do I establish a secure connection?!?

Thanks for your time!