This seems to happen with other software as well when Java engines are involved. I had it recently with a Java-based accounting tool. In my case 'sed' was missing, and the Java app was looking for it in /usr/local/bin. I had it actually in my /usr/bin directory, so I made a softlink for it, but even that didn't solve the situation for me.
With OpenOffice it should be easier. In your case I would ignore the RPM package, and rather install the tarball version. And even there you should have the option to ignore the Java-related parts (most of OpenOffice can do without, I guess).
Anyway, if someone comes up with a universal explanation why Java engines play so difficult, that would be nice.