REST-Voicemail app change password issues

The following was tested on Aastra 6739i and 6757i models, and specifically references the screen on the 6739i.

Voicemail app makes it too easy to clear password. Steps are:

1. Press softkey programmed for REST-Voicemail
2. Press Settings
3. Press Change Password
4. Press Submit. Password is cleared. Alternately, pressing the field for "Enter New Password", then pressing "Enter" without entering a password on the on-screen dialpad, clears the password.

The desired behavior for this is that the entry of a password is required to save the password, or that there is a confirmation prompt when entering a blank password.

Awareness of this was largely brought about by what I consider to be another bug. From the Voicemail > Settings > Change Password menu, pressing the back arrow key at the bottom left of the screen does not do anything. The only way to exit is to press the physical Goodbye button, or wait for the screen to timeout and exit. We have found that in an effort to exit this screen, users often clear their password accidentally.

These issues also occur on the 6757i, except that an on-screen dialpad is not brought up for password entry, and so pressing Enter is not an option to cause the issue. Pressing Submit without a password entered still clears the password, and the Exit button does not function.