Thank you for writing.
Than is correct, this feature has already been requested by another user of ours. Feel free to add your vote for it, in order to increase its priority. Once it gets enough votes we will consider its implementation.
Should you have any other questions, or suggestions, do not hesitate to contact us.
the Telerik team
Q2’11 SP1 of RadControls for WinForms is available for download (see what's new); also available is the Q3'11 Roadmap for Telerik Windows Forms controls.