Strange issue. No problem here.
Test: psi (my python shell), "exefied" with py2exe
Environment: w2k+sp4, Python 2.4, 2,5 all wxPython from 2.6 to 2.7.2 ansi
No problem with the proposed code, w2k+sp4, Py25, wxPy272-ansi
Jean-Michel Fauth, Switzerland