Short codes for international roaming -- is this normal?

Thanks again.  Last year on a cruise I remember seeing the $15/MB warning and I was able to use #763# to turn it off.  But now I can't seem to use these codes any more.  I guess I'll mention that when I call 611, that I need assistance in making sure I do not block roaming that is included in plan, but only this $15/MB stuff.  I'll be in Iceland which is included with my plan, but I'd still like to be able to make sure I don't wind up connecting to some random network not included in the plan.