mouse and Delete key

[Baloff]

Hello

I was reading the node on the mouse commands, this is not working, 

Mouse Commands for Editing
==========================
...
   If you select a region with any of these mouse commands, and then
immediately afterward type the <DELETE> function key, it deletes the
region that you selected. 

I mouse-1 say at the beginning of a line and mouse-3 past the end char. 
then hit the <Delete> key. it does not delete the line "region" but
only the last character.

what am I doing wrong, how can I delete a region. I usually do C-w but that 
puts it in the kill buffer.

thanks