W595 SSL problem

I have a W595 and would like to use SSL to connect to a server with a self-generated certificate. I have tried to install the root certificate - when I try to download this with the web browser it says "certificate saved", so it knows that it is a certificate; I don't know how else to check whether or not it is installed. However, when I try to connect to a web page on this server over SSL it says "connection error". When I try to retrieve IMAP email it says "Server not found" (although I can see from the logs that it has found the server and tries to connect). Any ideas?

Tim