I use Tomcat 7 and will enable the SSL Connector. Actuall i have edit this solution to the server.xml file:
You can not use a keystore if you are using the APR connector. It requires the same certificate formats as used by Apache.
EDIT: if you are running either Debian or Ubuntu on Linux you can use the ssl-cert
package to generate a self-signed cert that would work with the APR connector as documented at http://tomcat.apache.org/tomcat-7.0-doc/ssl-howto.html#Edit_the_Tomcat_Configuration_File (scroll down to the APR section).
EDIT: Try this as your server.xml
file. I removed some of the comments and commented out the APR listener. Your keystore should work now.