SetTitleSize() and SetLabelSize()

Dear ROOTers,

Please try the attached test program.
SetTitleSize() and SetLabelSize() do not work. But , for example, SetTitle() and CenterTitle() work properly. This problem happens only when I use same values for low-edge and high-edge.

Is there any way to solve this problem?
I would like to use same values for the edges because I am not sure the range of experiment data values.

void test()
{

   TCanvas* can = new TCanvas;
   TH1D* hist = new TH1D("", "", 40, 0, 0);

   hist->Fill(1, 1);
   hist->GetXaxis()->SetTitle("X");
   hist->GetYaxis()->SetTitle("Y");
   hist->GetXaxis()->CenterTitle();
   hist->GetYaxis()->CenterTitle();
   hist->GetXaxis()->SetTitleSize(0.05);
   hist->GetYaxis()->SetTitleSize(0.05);
   hist->GetXaxis()->SetLabelSize(0.05);
   hist->GetYaxis()->SetLabelSize(0.05);
   hist->Draw();

OKUMURA, Akira oxon_at_icrr.u-tokyo.ac.jp
Institute for Cosmic Ray Research, University of Tokyo 5-1-5 Kashiwanoha Kashiwa Chiba 277-8582 Japan Tel/Fax : +81 4-7136-3153
Skype : okumura.akira