Created Unassigned: HTMLEditorExtender -Clicking on Font size dropdown reset selected text font size [27686]

After changing the font size of selected text, if we reselect the text and click on font size dropdown it resets the font size of the selected sext.
For example, in the site http://www.asp.net/AjaxLibrary/AjaxControlToolkitSampleSite/HTMLEditorExtender/HTMLEditorExtender.aspx, select hello and change the font size to 7. Now clicking on the font size dropdown again will reset the selection.
Same thing happens anytime we select the text with a different font size from default and click on the font size dropdown it resets the size.

Please help me how to resolve this issue.

Thanks.