I also have the 8350i, almost a year now. I had a lot of texting an email problems in the beginning. Make sure you have all the latest updates (thru BlackBerry Desktop Manager). Once you know you have that, then turn off the phone, pull the battery, reinsert the battery... I do this every Sunday to make sure I get all my texts and emails. The reason you are having this problem is because it's on the Nextel network and not the Sprint network.