Sun's OpenOffice.org engineering team has developed a plug-in for building OpenOffice.org extensions. It is an easy to use set of wizards to create OpenOffice.org extensions that can be used to integrate new functionality, adopt existing functionality, and create Java applications that can remotely control OpenOffice.org. Everything is ready for you to start implementing OpenOffice.org extensions, including a Java code skeleton.
Hm, I just got this morning the weekly NetBeans newsletter and it had this part:
So, SUN is still supporting this. Maybe I'll take a look at this new plugin and see how it feels.