I've been informed that the addresses must be entered in the form 220.127.116.11 (not 11.22.*.*) and 0.0.0.0 (not *.*.*.*). They will still be displayed (both on the summary page and in edit mode) as 11.22.*.* or *.*.*.*.
I can't get the IP filtering function on our WorkCentre 7220 to work properly. I add rules for our subnets with ACCEPT. When I add a third rule with *.*.*.* for address and REJECT for Action, specifying lowest priority, the result that all source addresses are rejected, including the ones specified in the preceding rules.