[newbie] How are serial ports initialized?

[Henningsen]

My modem is on cua2, which is initialized to IRQ 4 when I start up, however,
the correct value is IRQ 10, so whenever I want to use my modem, i have to
do as root
setserial -v /dev/cua2 irq 10
How can I get that to be done on startup, preferably, where is the script
that sets that value?

Peter Henningsen
alifegames.com