I'd really like to hear how you make out. I'm running this on the Sharp ROM:
J9 - VM for the Java(TM) platform, Version 2.2
(c) Copyright IBM Corp. 1991, 2004 All Rights Reserved
Target: 20040706_1501_lHdFMq (Linux 2.4.18-rmk7-pxa3-embedix arm)
My problem is log4j (used by JXTA).
I assume you are running GPE in order to try the Blackdown JRE. As I understand it, the Blackdown JRE requires an X server and GPE is based on X.
Bottom line: I'd like to get Blackdown's JRE 1.3.1 or better running on the Zaurus hardware. I'll use whatever ROM image supports it.