I've tried to reproduce the problem you report, but to no avail. You can check the attached project which illustrates my attempt. Please note that, I am using our latest official version - 2014.2.0729. May I ask you to test with our latest version? Do you have some custom styles applied to RadGridView?
It will be great if you can modify the sample project in order to reproduce the issue and resend it back to me for further investigation.
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