Canadian Classic Prius mileage display stupidity???

I'm looking at buying a Prius and test drove a Canadian Classic Prius '01 the other day and I noticed the following strange behaviour of it's fuel consumption bar graph:

When the car is stationary/under electric power only, the L/100km bar is all the way up (seemingly indicating a very high fuel consumption), but when the ICE is running, the bar goes down to whatever its calculated consumption rate is..

Obviously this is a bug right? Certainly in a US miles per gallon display the bar should be high in the situation described (you're going any number of miles bug using no fuel- ie, divide by zero = infinity), but the metric version is the other way around (zero divided by anything = 0), so the bar should read zero... This does not appear to affect the average consumption number, so I assume that some programmer simply messed up the bar graph display code??

Is there a software update to fix this? Do all the newer models ('02-current) still behave this way??