I found this article in the CodeBin: Sample Access to OpenOffice or Lotus Symphony
This got me thinking again that having MailMerge support for source files other than Microsoft/XLS, and being able to de-couple from the ActiveX/OLE requirement would be nice.
Similar to as discussed previously on CSV Support, OpenOffice (ods), and Lotus Symphony support would probably not be terribly difficult to 'plug in' to this agent using the existing 'Spreadsheet' object API.
Also requested by Paul - June 11 2012 on Sacha's site.
Another useful link for Symphony here: http://www.ibm.com/developerworks/lotus/library/symphony-toolkit