Firefox and https in fc3

[Hongwei Li]

Hi,

I just setup our fc3 system to service https only (port 443), no http. 
When I check it in IE, I got Security Alert:

Information you exchange with this site cannot be viewed of changed by
others.
However, there is a problem with the site's security certificate.
...

Do you want to proceed?

If I click Yes, I can browse my web site. Then, during this session,
everything looks okay.  If I open another browser, it will repeat the
above.  That is okay with me althouhg not perfect.

However, I face a problem when I use Firefox.  I got:

You have received an invalid certificate.  Please contact the server
administator or email correspodent and give them the following
information:

Your certificate contains the same serial number as another certificate
issued by the certificate authority.
Please get a new certificate containing a unique serial number.

Then, there is no option to Continue.  I can only click OK, and my web
site does not show up.

What does that mean -- "the same serial number as another certificate..."?

Where to get a new certificate containing a unique serial number?

I apprecaite your help!

Hongwei Li