QSizeGrip not giving MouseButtonRelease Event on Windows

I am using QSizeGrip in my Widget and apparently on Windows I dont get the MouseButtonRelease event whereas I do get the same on MAC OS X.

I have tested this using installEventFilter and printing out the event names.

On windows whenever I resize I get the events in the below order
Paint
ToolTip or Leave

So, whenever I get in the above order I am assuming as resize happened but strictly speaking, I should be getting a MouseButtonRelease event as I get in MAC OSX.
Paint
MouseButtonRelease.

Please look into this.

Thanks!