Lpc2000

Hi! I read every doc I've found and I couldn't get a detailed 
description of the interrupt mechanism in the LPC2XXX. In particular, 
I'm looking for the following:

- What happens to interrupts while they're disabled? Do they 
get "cached"? I mean, if I'm in the middle of processing a UART0 
interrupt and UART1 receives a new character, I'd probably have the 
interrupts disabled. Will I miss the interrupt?

- Provided the interrupts get chached while disabled somehow... That 
would mean that they will trigger as soon as they're enabled, isn't it? 
I plan to keep interrupts disabled while processing other interrupts; 
could that work?

- What's the exact difference between edge and level triggered 
interrupts?

Thanks in advance