I've just posted a pre-release of OpenOffice.org Portable 2.1. New in this version is a long-awaited feature: the ability to use Java from the portable device. This means you can use the OpenOffice.org functionality that depends on Java (Wizards, some Base functions, etc) even from a PC that doesn't have Java installed.
Java is not yet GPLed, so it can not be hosted on SourceForge. Nor can it be repackaged due to licensing. So, you'll need to supply your own.
To enable Java, copy the Java files from a local install, usually C:\Program Files\Java\jre1.5.0_11. Copy the whole structure intact (so you'd have a lib and a bin directory in this Java directory when complete. Copy those files to either of these locations:
And then add in a file called javaportable.ini in that same Java directory above with the following in it:
Vendor=Sun Microsystems Inc.
That will enable OpenOffice.org Portable to work with a copy of Java on your portable device.