SMS TimeStamps is a tweak recently released in Cydia that allows iPhone owners to display in the Message application the time and date they sent SMS messages. Normally, the Messages application displays this only for the first SMS in a conversation, so if you send several messages to a person in a short period of time, you will not see a timestamp for each one. The tweak has a settings menu in the Settings application of iOS and from there you can activate/deactivate it and choose the time period that must pass to show you timestamps.
SMS Timestamps provides a way to modify the Messages app's default behavior of setting timestamps on the beginning of an active conversation, and then ceasing to do it until it deems it necessary again. With SMS Timestamps you can set this behavior manually so that you can see timestamps on ALL of your messages, or after a certain period of time has elapsed after a timestamp has been displayed (1 minute, 5 minutes, 10 minutes).
SMS TimeStamps is available for free in Cydia and even works with the iMessage system.
