Apache and SSL certificates peculiarity:

When adding SSL based virtual hosts and doing an apache2ctl graceful (or reload), if you get hit with an:

Oops, no RSA or DSA server certificate found for 'whateveryourdomainhere.com:0'?!

Then try this :) do a full stop/start

i.e.
# /etc/init.d/apache2 stop;
# /etc/init.d/apache2 start;

Cheers,