We actually removed the ability to store indexes in Infinispan because it performed poorly, would not cluster properly, and had a number of very difficult-to-fix issues. The only case it did work was in local (non-clustered) repositories, but even in that case storing the files on the local file system was significantly faster.
Apologies for not mentioning that in the release notes or the announcement. That was a oversight on my part.
No problem and no need to apologise for anything given the great work you do here.
Sorry for the delay responding, moved house a couple of days after I posted the message and in true british telecom style it's taken them 10 (working) days to restore my broadband......... :-(