convert a url path to an xpath

I have a path like www.domain.com/company/about/staff.htm and match
"company/about/staff" in the sitemap.
However, I cannot use this path directly in my xpath expression as the xml
looks like: 

...
<wx:sub-section>
  <w:p>
    <w:r>
      <w:t>company</w:t>
    </w:r>
  </w:p>
  ...
  <wx:sub-section>
    <w:p>
      <w:r>
        <w:t>about</w:t>
      </w:r>
    </w:p>
    ...
    <wx:sub-section>
      <w:p>
        <w:r>
          <w:t>staff</w:t>
        </w:r>
      </w:p>
      ...
...

So, somehow I need to create a xpath from the path "company/about/staff"
that looks like:
"wx:sub-section[w:p/w:r/w:t='company']/wx:sub-section[w:p/w:r/w:t='about']/w
x:sub-section[w:p/w:r/w:t='company']"

But how?
Any help greatly appreciated.

Linc