JavaScript error on clicking inside read-only CKEditor

We are testing your editor v. 3.6.4 in our ASP .NET application. We noticed that after setting editor to read only (with setReadOnly function or inside apsx markup) and clicking inside editor, the following JS exception is being thrown, if there is no content:

JavaScript runtime error: Unable to get property 'ownerDocument' of undefined or null reference

As far as we can tell this happens on IE9 and IE10.

This can easily be reproduced in your ASP .NET samples on FirstUse.aspx by substituting editor declaration with

<CKEditor:CKEditorControl ID="CKEditor1" runat="server" Height="200" ReadOnly="true" BasePath="~/ckeditor" />

Is there a solution or workaround for this problem?

Thanks in advance.