Closed Issue: HTMLEditor stripping out + (plus) characters, converting them to spaces [26912]

To reproduce, visit the demo page:

http://www.asp.net/ajax/ajaxcontroltoolkit/Samples/HTMLEditor/HTMLEditor.aspx

1) Type a +
2) Hit submit content
3) Watch the + disappear

I know we can all add, but if you ever wanted to teach math, I hope you're not using this control.