From what I've gleaned from the linux kernel source, we have the following
interrupt assignments on Jazz-compatible machines (bear in mind the NEC
machines deviate from this, and we're assuming the Magnum doesn't for the
time being...)

INT0 - local DMA
INT1 - MCT ADR local devices
INT2 - (E)ISA IRQ
INT3 - (E)ISA NMI
INT4 - MCT ADR interval timer
INT5 - cpu counter

While we're on the subject of deviations...  Ralf, the linux kernel currently
makes the assumption that the MCT ADR interrupt source and enable registers
are at 0xe0010000/2.  On the Pica/Olivetti/Magnum, they're at 0xe0040000/2.
I at least verified this on the Magnum, and others on the list can vouch for
the Pica and Olivetti.

Cheers,
-Mark