Secure connection failed on winxp only in firefox

[GM@N]

I am experiencing some strange behavior on WinXP, I can use IE to access any https sites, but I cannot use FireFox to access anything https, all of a sudden. The message I get is "Secure Connection Failed" in Firefox.

I am using the same proxy server in both IE and firefox with the same user ID

Things i have tried to resolve this;
New firefox profile
Complete reinstall of firefox
Recreation of Windows profile combined with the above

I googled without luck on what might be the cause, could someone please help on how to fix this?

 

[tolien]

First result on Google.

Sounds like a dud certificate. Checked your clock's right?

 

[uv]

Make sure the "use this proxy server for all protocols" checkbox is ticked in the proxy settings of firefox.