How to disable/grayed-out the 'X' close button in dialog?

[Shvalb]

Hi.

How can I disable or grayed-out the 'X' button that closes a simple dialog ??

I know how to do it with the Minimize/Maximize buttons, i.e.: WS_MINIMIZEBOX/WS_MAXIMIZEBOX, but how to do it with the 'Close' button - that's my question.


Thanks.