Here's the ia64 part of the ACPI IRQ cleanup I proposed here:

http://www.gelato.unsw.edu.au/linux-ia64/0403/8979.html

After the arch bits are in, I'll post the corresponding ACPI changes.
I removed the "Found IRQ" printk now because when the ACPI
change goes in, dev->irq won't be initialized until *after*
acpi_pci_irq_enable().