JohnDoh: nice, it works great.
skaero: you're right, but I need this change in the layout to be applied to every user. in fact, it would be better if I could turn that feature off.
This is to be used by elderly people, so I need to put away lots of options and just make available the basic functions of sending and reading e-mails. And of course, make things big for users with vision problem.
I will definitely need to make lots of changes, that's why I asked if I'm entering in a world of hurt.
Thanks to both of you!