Users running the newest release of DrJava on Java 1.4 may experience a "double backspace problem", where pressing the backspace key in the Definitions Pane causes two characters to be removed instead of one.
To work around this problem, select "Edit, Preferences" and then set the key binding for Delete Previous to "none" by clicking on the "..." button, and then selecting "Clear".
We are working on a long term solution to this problem.