Microsoft Windows family

• Windows 2000
• Windows XP (x86/x86_64) - including SP1/SP2/SP3.
• Windows Vista (x86/x86_64) - including SP1.
• Windows Server 2003 (x86/x86_64).
• Windows Server 2008 (x86/x86_64).
• Windows on Itanium (ia64) - checked with Server 2003 SP1 (internal jdk1.5.0_04 and public 1.6.0_10-beta)

Linux

• various distributions and architectures (x86, x86_64, ppc, ppc64, sparc, ia64)

Mac OS X

• 10.4 (Tiger, x86, ppc)
• 10.5 (Leopard, x86, x86_64, ppc, ppc64?)

Solaris

• 8,9,10 (sparc, sparcv9, x86, x86_64), OpenSolaris

AIX

• known to work on Java5 and Java6 (both 32 and 64 bit) on AIX 5.3 (Note: could be some issues with using unpack200 from Java6)

*BSD systems

• known to work on FreeBSD 7.0 (i386) on OpenJDK6 (1.6.0_07)
• known to work on OpenBSD 4.3 (i386) on JDK 1.5 (1.5.0_14) and JDK1.6 (1.6.0_03) from "ports".

HP-UX

• known to work on HP-UX B11.11 PA_RISC2.0 (9000/800) with both Java5 and Java6, will likely work with on Itanum (IA64) as well. Thanks to Tomas Hurka for help tweaking NBI to work on HP-UX!