[xsl] white space to + in query string

Folks,

Is it possible to use an attribute value template to construct a query
string in a URL, for example where the AVT picks out the text node
child of an element's attribute node:

<xsl:template match="some element">
<a href="http://some_site/some_file.html?some_name={@some_attribute}">Blah
Blah</a>
</xsl:template>

I would think this is feasible, but what about the white space in the
text? How can the white space be transformed into "+"'s? 

Thanks,

Bruce Rosenstock
Digital Library Analyst, UC Davis

 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list