GWT对话框-启用动画时的大小调整问题

GWT客户端代码:

DialogBox dialog = new DialogBox();
dialog.setAnimationEnabled(true);
SimplePanel panel = new SimplePanel();
panel.setPixelSize(800, 600);
dialog.setWidget(panel);
dialog.center();

使用上述代码时,对话框的宽度设置不正确-对话框在大约400 px处被切断。

DialogBox dialog = new DialogBox();
SimplePanel panel = new SimplePanel();
panel.setPixelSize(800, 600);
dialog.setWidget(panel);
dialog.center();

火狐:3.6.9
铬:6.0.472.55β