"SMS-Chat is a Windows Mobile SMS messenger that organizes your SMS correspondence into threaded SMS conversations. This way you have a separate chat for every contact with whom you exchange short text messages. You can easily follow a conversation scrolling thru chats with a finger: all messages are grouped by date. Manage your mobile texting with a flick of a finger!"
It is a good thing third party developers come up with applications that should be built into our devices to begin with. Oh I forgot, WM 6.1 will have threaded SMS when it arrives in 2025. The good news is you don't have to wait that long because Vito has come up with an interim solution. This one looks pretty good.