Sometimes text messages that I send seem to be seriously delayed, sometimes on the order of hours.
When they do finally go through I have been told that they have a tendancey to show up all at once.
This isn't always the case. Sometimes they work fine, sometimes they don't. This is not environmental or coverage related, as it happens both while I am at home and at work. The same is true for the people I am having these issues with. There seems to be no coralation between location of either side and delayed messages.
Done the basic troubleshooting of updating the profile/PRL and having Sprint support refresh the device.