Not sure if this is similar to other issues, but:
Ubuntu 12.04 beta AND Ubuntu 11.10. Xiphos 3.1.5-webkit
Unable to produce any indexes.
Command line produces:
mkfastmod: error: Wycliffe does not support a search framework.
Module Manager replys:
Index failed
I was told in live chat that it was because the Ubuntu build of Sword was not built with Clucene. Or perhaps an incompatible version, but I believe that the 0.9 version I am on is fine.
more recent conversations with our ubuntu builder indicate that current builds in ubuntu's own repos have correct clucene support.