Here's a sneaky way to have what you want, at least with version 2008b there's the only way.
edit pie
go to line 91 of the pie.m
replace the line with the code inside=0; by this
global inside %so we can access the variable outside the function
try %this is needed to keep the function working just like before
inside==0; %without giving errors when there's no value assigned for
catch %the variable inside, the default value is zero just like before
inside=0;
end
Save pie.m
Now to try it do this example
clf
global inside %access the same variable as the one of the function
inside=0; %make it 0 to draw the percentages outside
x = [1 3 0.5 2.5 2];
explode = [0 1 0 0 0];
%labels={'1','2','3','4','5'}; %in case you want to override auto %
%pie(x,explode,labels) %use your own percentage labels
pie(x,explode); % draws the pie with auto percentage labels
hold on
inside=1; %now make it 1 so we can put labels inside
labels={'one','two','three','four','five'};
pie(x,explode,labels)
colormap jet
