Version:            (using KDE 4.4.3)
OS:                Linux
Installed from:    Ubuntu Packages

Clipboard content is lost when the source application - the application that I copy data from - is closed.

It can be reproduced like this :
1. Open 2 instances of kwrite
2. Write something in instance 1
3. Copy the text with CTRL-C
4. Verify that the text can be inserted in instance 2 with CTRL-V
5. Close instance 1
6. Try to insert text again in instance 2 using CTRL-V

The expected result is that the text is inserted, but it isn't. Somehow the data is not copied away from the application.

The same scenario applies when using the X11 middle-click approach.

It seems that all kde application is affected, but also data copied from xterm disappears if xterm is closed.