Edited.

The Sent does need to remain in order for it to function correctly. If not, what will happen, is that your blackberry won't automatically send a receive.

Second, it should not automatically convert it to a regular text message, unless the person that you are sending it to doesn't have the same email client that you are using, then it will convert it to a regular text message.

Third, the people that are commenting probably have a read receipt set up so they can tell when you read their email. Otherwise they won't be able to tell when you read it.

I would contact your wireless company for any more detailed questions. The customer service teams are trained to answer any questions you might have. If you need more detailed information, I would go into one of the stores....

I worked for Verizon and we handled these questions on a daily basis......