SmartSig allows you to create custom email signatures

The auto signature feature on your BlackBerry can be useful. Like the desktop email equivalent, it can append your contact information to all emails. The difference with BlackBerry is that it can let others know that you’re on the device, which helps explain why some messages are short (and lack capitalization in certain areas). In fact, that’s the default signature with most BIS BlackBerry devices. You can change the auto signature , but there are still issues. For instance, your BlackBerry appends the signature after all text, including forwarded and replied text

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SmartSig allows you to create custom email signatures