Request for interpretation / clarification of USEMAP semantics

The spec on the usemap attribute is confusing to me (1). The value of 
the attribute is a URI, however the prose says:

'The value of usemap must match the value of the name <http://www.w3.org/TR/html4/struct/objects.html#adef-name-MAP> attribute of the associated MAP <http://www.w3.org/TR/html4/struct/objects.html#edef-MAP> element.'

I cannot take this literally, because in general practice the value of 
the usemap attribute actually has a '#' and then the name of a MAP 
element, which is a URI specification. So, my question is this: can the 
value of the usemap attribute refer to a MAP element on another page? 
For example, are the following legal:

<img SRC="map1.gif" USEMAP="map2.html#imagemap">

<img SRC="map1.gif" USEMAP="http://www.attinasi.org/map2.html#imagemap">

If not, then can the value also refer to a map on the same page, but 
referenced using a full URL? For example, consider this:

(in the file map2.html)

<img SRC="map1.gif" USEMAP="map2.html#imagemap">


Thanks,
- marc


[1] http://www.w3.org/TR/html4/struct/objects.html#adef-usemap