Real group gadget in b+, but weird bug...

You need the sendmessage userlib

.lib "user32.dll"
SendMessage%(hwnd,msg,wParam,mPAram):"SendMessageA"

And this test program

window = CreateWindow("test window",100,100,300,300,0,1+2)
group  = creategroupbox("testing",10,10,ClientWidth(window)-20,ClientHeight(window)-20,window)

Repeat
	Select WaitEvent()
		Case $401 : Notify "clicked group"
		Case $803 : End
	End Select
Forever

Function CreateGroupBox(label$,x,y,width,height,parent)
	;create blitz gadgets
	gadget = CreateButton(label$,x,y,width,height,parent,1)
	HideGadget gadget
	SendMessage(QueryObject(gadget,1),244,7,True)
	ShowGadget gadget
	;return gadget
	Return gadget
End Function

Now it works out of the box like that,.. but now try resizing the window.. weird!



Anyone know what is going on here?