If you’re getting tired of the ‘Sent wireless from my Blackberry handheld’ or want to put contact information as your signature instead in all emails, do the following:
1. Log in to your BlackBerry Internet Service for T-Mobile account.
2. Under the Settings menu, click E-mail Accounts (as shown below).
3. Click the Edit icon beside the email account for which you want to change the auto signature.
4. In the Signature textbox, enter in the signature you want to use with the email account.
5. Click Save. The auto signature is changed.