Install apps to sd card by default How can I do this? I'm using a Samsung Galaxy Ace

I've tried this method http://forum.xda-developers.com/showthread.php?t=1278349
I confirmed that it was indeed set to 2. But it wouldnt work.

Then I rooted my phone, installed an app with which I could modify the default installation path, but it also wouldnt work. 

What can I do?
With 2.3, it will install apps by default to the external SD card.  However, this will only happen if the app can run from the SD card.  Many apps must be installed onto the internal storage in order to work properly.