I want to report here the message from the developers:
OOChemistry is an extension for OpenOffice.org which provides cross-platform OLE-like integration of OOo with JChemPaint chemical diagram editor. With OOChemistry you can draw structure, embed into document (text or presentation) and than double click and edit whenever you want on any platform having OpenOffice.org and Java Runtime (Windows, Linux, Mac OS X, other Unix flavours). It is only first alpha version and is not recommended for production use (e.g., compatibility with futher versions is not guaranteed).
OOChemistry needs your help! Experience in Java, in development of projects dealing with JChemPaint/CDK, or in development of OpenOffice.org extensions will be highly appreciated. Of course, you can help not only in coding, but also in translation of interface and writing docs.
Project page on SF
It sounds very interesting.
I'll try the installation asap.