[SOLVED]Resize event and GetClientRec fails

In a form I'm using a ribbonbar and a dockingpane. In the client area should be placed a usercontrol.

The dockingpane is associated with the commandar with the following code:
cjDockingPaneManager.SetCommandBars(this.cjCommandBars.GetDispatch());

The resizing of the usercontrol in the client area sholud be done with:

        private void cjDockingPaneManager_ResizeEvent(object sender, EventArgs e)
        {
            int left, top, right, bottom;
            cjDockingPaneManager.GetClientRect(out left, out top, out right, out bottom);
            userControl.SetBounds(left, top , right - left, bottom - top);
        }

But the resize event occurs only once at the program start and the second thing is that the values from the GetClientRect method delivers wrong values (left and top = 0, right and bottom are the values from this.ClientSize).

I have tried to resize the client usercontrol in an other resize event (form, commandbar). But the GetClientRect method delivers always wrong values. I have also tried to use a richtextbox instead of the usercontrol, but the result is the same.

It seems that the GetClientRect method only work correct if no commandbar is present.

Is there a way to solve this behavior?

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OS: Win XP prof. SP3
Codejock Version 13.1.0
Microsoft Visual Studio 2008 Version 9.0.21022.8 RTM
Microsoft .NET Framework Version 3.5 SP1
Installed Edition: Enterprise
Microsoft Visual C# 2008
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