Just found a solution to the problem: when using wx.EVT_SPINCTRL instead of wx.EVT_SPIN_UP, wx.EVT_SPIN_DOWN or wx.EVT_SPIN the program behaves correctly.
wxWidget documentation for wxSpinCtrl states that "You may also use the wxSpinButton event macros, however the corresponding events will not be generated under all platforms"; I ran the program on WinXP SP2. However, the events seem to be handled (at least EVT_SPIN_UP, wx.EVT_SPIN_DOWN). So I do not understand why handling these events leads to a buggy behaviour. -- http://mail.python.org/mailman/listinfo/python-list
