Further to my earlier comment, I now feel that 

> > <div sem="address">
> > <l sem="person">Haruki Murakami</l>
> > <l sem="street">Omote-Sando</l>
> > <l sem="city">  Tokyo</l>
> > </div>

is itself sub-optimal; why invent a parameter "sem" when
the existing parameter "class" is intended to convey exactly
that ?  In which case, the optimal markup would become :

	<div class="address">
	<l class="person">Haruki Murakami</l>
	<l class="street">Omote-Sando</l>
	<l class="city">  Tokyo</l>
	</div>

if each address element is /defined/ to occupy one line;
however, since there may be contexts within which it
is desirable to render an address in a compact form,
it would surely be better to represent this as

	<div class="address">
	<span class="person">Haruki Murakami</span>
	<span class="street">Omote-Sando</span>
	<span class="city">Tokyo</span>
	</div>

and leave it up to CSS styling rules to decide whether
spans of class "person", "street", "city", etc., should
be block or inline.

Philip Taylor, RHBNC