Follow these steps:
1. From the
Main menu choose
Options.
2. In the
Options window
Privacy & Security tab, click the
History option.
3. In the right pane, uncheck
Save history.
4. Click the
Set per contact link.

5. From the
Don't save history pane select the friend for which you want to save history and click the left pointing arrows button; The name now appears in the
Save history pane.
6. Click
OK to close the
Set per contact window, then click
OK to close the
Options window.