diff --git a/src/generic/calctrl.cpp b/src/generic/calctrl.cpp
index f10b5015ca..1b4e84226f 100644
--- a/src/generic/calctrl.cpp
+++ b/src/generic/calctrl.cpp
@@ -202,6 +202,9 @@ bool wxCalendarCtrl::Create(wxWindow *parent,
                             long style,
                             const wxString& name)
 {
+    // set the style first to avoid assert in our SetWindowStyleFlag()
+    m_windowStyle = style;
+
     if ( !wxControl::Create(parent, id, pos, size,
                             style | wxCLIP_CHILDREN | wxWANTS_CHARS | wxFULL_REPAINT_ON_RESIZE,
                             wxDefaultValidator, name) )