They do the same as Ilford: they evaluate "ISO" on a practical, rather than ISO standard form. Most (all?) Ilford films have disclaimer like this:
Originally Posted by TimFox
"It should be noted that the exposure index (EI) range recommended for 100 DELTA Professional is based on a practical evaluation of film speed and is not based on foot speed, as is the ISO standard."
Edit: actually I was wrong, there is ISO for digicams: http://www.dpreview.com/forums/thread/2838786
I wonder how accurate my digital metering for film is then... :-/