Highway Shields in Legends

[Syvertson]

I would like the ability to add shields to legends depicting line features.  We use the same line type to depict paved two lane highways whether they are state or US highways, but use a different shield.  Or we may have one stae highway that is two lane in some places and four lane in others.  I would like for the legend to show the different combination of line type / shield.  This seems as though it would not be too hard to implement and that it woudl be widely used.