Lpc2000

Thanks, Karl.

> Do you have the "LDR PC, [PC, #-0x0FF0]" at address 0x18

That was it.  I saw that in the manual, but I assume the IAR startup 
code was already handling that.  Of course they weren't.

ISR's jumping now! 
 
> Have you reserved a suitable IRQ stack
Yes, had done that.
 
> Have you enabled IRQ in the CPU (like "msr cpsr_c, #0x1F")
Yes, had that.
 
Chris.