Ooh, I haven't used Handcent since I've had my Rezound... I love a mystery!
Found this in a XDA thread:
""I figured it out... After reinstalling handcent.... Too bad I have to reconfigure handcent.
In handcent go to settings...application settings......default messaging application..... Then pick at the bottom "use for all SMS & mms"
Now it works!
I'm curious to know if it would have worked without reinstalling.... Seems like I remember that setting was on "disable" not sure how it got set to that!""
From Handcent webpage: (emphasis mine)
Handcent SMS(for Android) is a powerful, customizable,and free SMS/MMS app that fully unleashes the messaging potential of Android devices.
More than just an unsurpassed alternative to the stock Android messaging app, Handcent SMS features optional, seamless online integration with your My Handcent Online account allowing users to circumvent the limitations of the smartphone operating systems and wireless carriers. Other popular features include: keyword search, T9 text input, popup notifications, crossplatform emoji support, theme support, privacy box, task scheduling and more!