Is this a bug? Bottom border around the editor gets hidden

Hi.

Just testing some stuff in the latest version and found this odd behaviour.

How to reproduce:

1. Go to:
http://www.fckeditor.net/demo/toolbar?toolbar=Basic

2. Click the "Collapse Toolbar" icon on the left of the toolbar, to hide the toolbar.

3. Click the "Expand Toolbar" icon --- Mousepointer just above the same place you clicked in #2

4. Now if you still keep the mousepointer just above the "Expand Toolbar" icon after you clicked it in #3, then you will see that the borders around the editor are visible.

5. Now move the mousepointer over some of the icons in the toolbar.
What happens is that the bottom border of the editor is hidden.
Looks to me that the toolbar is growing in height with approx 1px...

A minor thing, but can be confusing for an end-user in some cases though.

Anyway... what a great editor this is
I'm drooling now, especially after FCK introduced same ENTER KEY behaviour in the supported browsers....
Greate job FCK!