Error List and Determining What to Underline

Hi all,

I've determined that using the DTE it's possible to get the list of error messages from the ErrorList. However, is there a programmatic way to determine what to highlight (for example, with the wavy blue underline) on the screen? The ErrorItem object gives Line and Column, but I can't find a way to determine the Length of what to underline. For example, we can get the starting line and column number with:

_dte.ToolWindows.ErrorList.ErrorItems.Item(1).Line
_dte.ToolWindows.ErrorList.ErrorItems.Item(1).Column

However, there seems to be no direct way to know the length. Any advice? Is there some way to get access to an underlying "Error Object"? I've attached an example where I'd like to adorn unknownMethod through a custom visualization.