Hello Jean-Marc Windholz,
We know about a similar issue in RadDock
and we plan to address it in our upcoming release in July. However, it is possible that this is a different issue. So, please send us your application and describe the exact steps to reproduce it. Thank you for your cooperation.
Should you have other questions, we will be glad to help.
the Telerik team
Q1’11 SP1 of RadControls for WinForms is available for download
; also available is the Q2'11 Roadmap
for Telerik Windows Forms controls.