Did anybody try running JBoss on your iPhone?
I did!
Unfortunately JBoss AS 5.0 CR1 didn't boot, but I could run 4.2.3 with "-Xmx32m -Xms32m".
Due to the lack of memory, I couldn't run the default configuration, but managed to boot the microkernel with the minimal configuration on the tiny handy Unix based device.
For more information, visit:
http://yusuke.homeip.net/blog/2008/08/24/1219512420000.html