when m_oldFocus has been destroyed, so we check the HWND with ::IsWindow. Also some setup.h, makefile and TIFF library changes for Watcom compilation git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_2_BRANCH@7642 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775