In oder to secure this personal website I have recently joined the CAcert community. This community driven certificate authority issues free public key certificates. After signing up I created two server certificates, one for the webserver and the other one for secure mail and ldap services.
So if you are using any web or mail related service on the vleeuwen.net domain I would recommend to import the CAcert root certificate. See the CAcert site for more information.

Hopefully one day Mozilla will make the right decision and include the CAcert root keys in their products.