I have a OES2/Linux server set up some half a year or so ago.
Today I tried to install a new printer, and to my surprise, I got this:

Untrusted certificate encountered while connecting to iPrint server.
Continue to the iPrint Certificate Manager if you would like to view this certificate and authorize its use.

If I continue and choose to trust the provided certificate I get this:

Error: Certificate Manager Failure
[Root exception: java.io.IOException: Keystore was tampered with, or password was incorrect] Unable to add certificate to trusted certificate store

It happens whenever I want to manage printer, printermanager or driverstore. But it happens only on some tabs. I can, for example, edit Access Control tab, or Drivers tab in driverstore object.

I did today in the morning some update with rug (unfortunately, I didn't do a checkpoint, so I can't rollback and see if it's somehow connected). I provided the upgraded packages list as attachment.
The biggest problem is, I don't even know where to start debugging this problem.