First of all I want to thank you about your interest in RadRichTextBox.
Now, straight to your issue - please, can you try to answer to the following questions:
- What is the operating system which you are using?
- What is the Input Method Editor which you are using? Is it Microsoft Windows IME or another one?
In addition, I want to mention that with our upcoming Q3 2014 release, we will introduce a functionally which will enable you to extend and handle a current Input Method.
Looking forward to your reply.
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