| | Re: deactivate "send using" option
If you hate that drop down lost... just don't scroll up to look at it.
If you're more concerned about making sure ALL of your email is sent from one specific account, set that Options > Advanced > Default Services. Then, all email will by default be sent by that email account. EXCEPT, The Blackberry will remember the email account used to previously send to a contact. So, if the last time you email Joe from your BlackBerry and used the Yahoo1 account, it will use it again, BUT, having the drop down Sending Using list, you can change that, and therefore changed for the future.
Makes sense to me.