I have downloaded and installed the: FreeTextBox 3.1.6 at http://freetextbox.com/files/8/default.aspx wich is the textBox where you write these posts with bold, italic and other tools.
I have put the "FreeTextBox.dll" in the BIN folder and added this reference by "Choose Item" in the toolbox.
Now I have added this line at the top of sourceview just under the line: <%@ Page
<%@ Register Assembly Go to the complete details ...