How to reproduce.
Open Log Viewer.
Collect some logs (e.g. run a test).
To easy evaluate not collect more than couple of records.
Set cursor to find field and press Enter.
Log records will be duplicated with each pressing of Enter.
*** (#1 of 1): 2007-05-21 16:30:51 MSD

Addition:
The usecase of pressing Enter on a clean Find field makes sence because of following: once user looked for something meaningful - he wants to get log window showing all entries again - how can he do that? - intuitive by clearing a Find field and pressing enter.