Ramu,
Check the source code of the following files:
\Framework 1.x\cs\customization.aspx
\Framework 1.x\vb\customization.aspx
\Framework 2.0\cs\customization.aspx
\Framework 2.0\cs\customization.aspx
You can add any web control into Cute Editor as a custom button.
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asp wysiwyg html editor: http://cutesoft.net/ASP
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