Zulu Keypad UI does not support select-all, delete or select-all, overwrite

After upgrading to the latest version of Zulu (v3.3.0+67), the keypad has a UI issue.

If you select a number (for example the last number dialed) and hit delete or backspace, the number remains.  If you select the number and start typing a new number, the new number is appended to the old number. The only way to enter a new number is to hit backspace multiple times to erase the number.

The correct behavior in the first two cases is to delete the number and in the third case to overwrite the number with the new number.