Apple iPhone imposes a limit on the total number of SMS text messages that can be stored at a given time. If this limit is exceeded, existing conversations must be deleted in order to make room for new messages.

Syphone Beta is a freeware SMS management utility for Mac OSX that allows you to view, delete, save, archive, import/export and backup SMS text messages from your Apple iPhone on your Mac PC. It does not alter or affect your iPhone in any way. [via Macworld]

Main features of Syphone include:

+ View synced iPhone SMS Text messages on your Mac OSX computer
+ Archive SMS messages
+ Import/export SMS messages
+ View SMS messages offline in an iChat-like interface with selectable colors
+ Open Address Book contacts
+ View the number of sent and received messages for each contact
+ Support multiple iPhones

Download Syphone for Mac OSX/Apple iPhone here [warning:ftp site]