Despite my running the following command:
stsadm -o setproperty -pn job-immediate-alerts -pv "Every 1 minutes between 0 and 59"
the immediate alerts timer job runs every five minutes.
What do I need to do to get it to run every minute?
I forget to include the -url switch. See http://technet.microsoft.com/en-us/library/cc262432(office.12).aspx
I think you cannot have a custom schedule. You have to pick one of the existing scheduling options available in the dropdown and/or documented at the link above.