Can't probe legacy SSL port

We’ve been running Openfire 3.6.4 for well over 2 years.

All of a sudden, on a weekly basis, I have to reboot the server because people are unable to connect.

One thing I did notice was that if i wen’t into PSI and unchecked

Probe legacy SSL Port,

then they could connect.

I read that this might be a result of an expired ssl certificate. Openfire reports an expire date of 2014. But under status, there is a icon with a yellow triangle with an explination point in it.

Not able to find the meaning of that icon, but everything else seems ok.

any ideas?