I am running Juicy R3 & I had problems until I installed Vit0 SMS-Chat. Shown here also using TouchPal 3.5
I absolutely LOVE this app (it's one of my favorite apps, I have used it since my Titan days) & get no lag whatever using it, but it took me a while to realize it worked with WM 6.5/sense 2.5. It
DID NOT work the first time I installed it (it would receive, but not send so it was useless)
I had given up, but somebody else figured out that SMS-Chat works perfectly as long as you
disable the laggy HTC messaging first. This works perfectly, I get no lag at all for texting & use ArcSoft for MMS.
~John