Before upgrade
When I was running git clone git@...
(using ssh) once per computer restart a window dialog appeared containing a textbox for inserting my SSH passphrase and confirmed with OK. Then the passphrase was no longer required until the next start of my system.
After upgrading to 13.10
After upgrading to Ubuntu 13.10 that window doesn't appear anymore but a message in terminal appears:
Enter passphrase for key '/home/username/.ssh/id_rsa':
...every time when cloning a git repository this appears.
How can I fix this? I want to enter my passphrase only once.