[ubuntu] How can I change master key in KeePassX?

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http://ubuntuforums.org – Hello everyone, I am using KeePassX on Ubuntu 12.04, and I think it is an excellent program. I have a small question - can I change my master key to a more complicated one? When I started using the program, I chose a simple one that is easy to guess. Of course I could start a new base with a new password and copy-paste everything there but it is a lot of manual work. Thank you in advance for any ideas! (Hardware)