I have used Opera Mini on both my devices. I love it -- most of the time. It's even better when I can use the XHTML browser at www.surfwap.com
to access a cleaner version of my newspaper sites.
Still, I had to switch back to the Opera Mini 3 from the beta because it was too unstable. There have been times when it has crashed repeatedly during simple operations.
Maybe I am asking too much from this third-party software. Then again, is it true that it comes pre-installed on the Curve?
The only thing I could suggest is that you remove it from your device and and download Opera Mini again.