I have just downloaded the Project Darwin, and reading on the new features of Ehcache, I checked the JTA support. It says:
Terracotta Clusters only
It only has effect then using Ehcache with the Terracotta Server Array ("TSA").
In the open source vs commercial comparison, it says that Ehcache is available in both versions, but that "Linear scale with the Terracotta server array data striping feature" is only available in the commercial version.
So, does that meant that JTA only works with the commercial version?
JTA works in the open source and paid versions. Currently it only works in the "Terracotta Clustered" version, free and open source.
It doesn't work with unclustered ehcache but that is coming.
It can be a bit confusing but we refer to the server layer as the server array in all cases. In open source you can using a mirror'ed array. The paid version supports a striped array.