[Mono-dev] Form.ShowDialog Error

[lb1234567 at sjtu.edu.cn]

Hello, I am a new user of mono, and I encountered a very big problem. When I am running a window and evoke another windows, this bug will occur. For example, the new window is name Win, then I write:
Win w=new Win();
w.ShowDialog();
w can be opened, but when I close it, the application will be terminated by an error.
If I use w.Show(), the error will occur in the console, but application will not be stopped.
Do you have this problem? Can anyone help me? Thanks.