Is it true that the indexer does not index the contents of open document formats like odt and ods? I've noticed it does Microsoft xls and doc files but not my open document formats. What gives?

Is there a list somewhere that has all the file types it can index? I know pdfs aren't coming until Groupwise 8 but no open document support? That's very strange to me. It's like it can index proprietary formats but not the open source ones.

Thanks for any input!