Incorrect color switching when using errorbar() and plotyy()?

The code below is intended to plot points with errorbars and draw 2 lines. It should give the lines different colors, yet it does not. If you run the plotyy() command twice, one line + axis changes color. Is this behavior intended?

close all;
figure;

% Create dummy data
x=[1 2 3];
y=[1 2 3];
s=[0.2 0.1 0.3];

% add noise
y1=y*randi(10,3)/10;
y2=y*randi(10,3)/10;

% Plot
errorbar(x,y,s);
hold on
plotyy(x,y1,x,y2)