Please use these code with my prior permission.
When using Dock-iframe in IE, IE will display horizontal scroll bar if the webpage inside is a standard one, i.e. has <!DOCTYPE> tag. IE can never count width correctly. To avoid this simply upgrade your webpages to xHTML 1.0 standard; <!DOCTYPE> somehow would be omitted by IE since the webpage then begin with <?XML>. This is how we deal with IE: use two bugs to cancel each other. I hope this will work on IE7, too; haven’t tested it though.