Attributes: syntax hacks

A simple issue that pops up when using 
XML to represent object-oriented languages 
is the mismatch between fields and attributes. 
If a field has structure, it shouldn't be 
an attribute.  But when the expression is 
simply repeatability (ie, the attribute 
contains an array of string values), the 
messy problem of spaces pops back out.

To me these are ugly hacks:

URL='"me1.jpg" "me2.png"' and 
URL='"me.jpg""me2.jpg"'

and dicey because:

o  they are vulnerable to authoring errors, 
so weakening the XML document where it is 
suppose to be strong: parse and go.

o they are vulnerable to the machinations 
of XML-like systems such as the SOAP 
processor which does nothing with the 
entity declaration.

But considering that filenames can have 
spaces in them in both MS and Unix operating 
systems, other than stuffing %20 in the strings, 
that is a likely solution.

Other than 

<url>me1.jpg</url>
<url>me2.jpg</url>

what are better solutions?

len