bars turn black when overplotted

Hello,

I want to overplot three bar graphs:

figure; bar(data1);hold on;
bar(data2,'r');hold on;
bar(data3,'g');hold on;

If I do that, the bars graphs are plotted in one figure, but annoyingly, only the first one maintains its color (blue by default), whereas the following two are both plotted in black. Could anyone help?

[EDITOR: This code is executable:

clf;
bar(rand(1,3));
hold on; 
bar(rand(1,3),'r');
hold on; 
bar(rand(1,3),'g');

)

[Doug Hull]

I tried this with the modified code in your question. I do not see the problem.