[FF] Ctrl+backspace inside table removes too much stuff

[Marek Lewandowski]

1. open any sample with CKEditor (i.e. samples/replacebyclass.html)
2. use following source code

   <table border="1" cellpadding="1" cellspacing="1" style="width:500px">
   	<tbody>
   		<tr>
   			<td>&nbsp;</td>
   			<td>&nbsp;</td>
   			<td>&nbsp;</td>
   		</tr>
   		<tr>
   			<td>&nbsp;</td>
   			<td>&nbsp;</td>
   			<td>&nbsp;</td>
   		</tr>
   		<tr>
   			<td>&nbsp;</td>
   			<td>&nbsp;</td>
   			<td>&nbsp;</td>
   		</tr>
   	</tbody>
   </table>
   
   <p>&nbsp;</p>
   

3. switch back to wysiwyg mode
4. place cursor in very last cell (9th)
5. press ctrl + backspace twice

Expected result:
Caret should not move outside of the cell?

Current result:
Leaves table with one column and two rows

additional info:

1. it acts weird with ctrl+backspace in many other cases with tables

[Jakub Ś]

Problem can be reproduced from CKEditor 3.0 in Firefox only (It doesn't occur with native tables).