On my old window's mobile phone, if I deleted and email from my inbox ("on device" - the computer) then it would sync with my phone and delete from there as well.
Is this not an option with the curve?
Note: I don�t mean outlook email. Just hotmail, yahoo, Gmail...etc.
No. You have to delete the items on your BB separately. However, the reverse is true - when you delete an item on your BB it will also delete it on the main account.