Generated list building blocks for structured documents

In addition to the typical generated list building blocks, you can use <$elemtextonly>, <$elemtext>, and <$elemtag> when the target document is structured. Is there any way to grab attribute values from the target document to include in a generated list? I've tried using <$attribute[ATTRNAME]> and <$attribute[ATTRNAME:ELEMTAG]>, but neither work. Is this just not possible through standard list building methods or am I doing it wrong?

Thanks!

...scott