I'm trying to work with hProduct

was testing tool for google microformats (http://www.google.com/webmasters/tools/richsnippets), but it is not recognizing the data:

1. does not recognize the photo
2. does not recognize the price
3. does not recognize the category
4. only recognizes the rating

HTML:

<div class="hproduct">
  <span class="brand">ACME</span> <span class="fn">Executive Anvil</span>
  <img class="photo" src="http://microformats.org/wiki/skins/Microformats/images/logo.gif" />
  <span class="review hreview-aggregate">
    Average rating: <span class="rating">4.4</span>, based on <span class="count">89
      </span> reviews
  </span>

  Regular price: $179.99
  Sale: $<span class="price">119.99</span> (Sale ends 5 November!)

  <span class="description">Sleeker than ACME's Classic Anvil, the Executive Anvil is 
    perfect for the business traveler looking for something to drop from a height.</span>

  Category: <span class="category">
    <span class="value-title" title="Hardware > Tools > Anvils">Anvils</span>
  </span>
</div>

and still shows this warning:

waring: In order to generate a preview with rich snippets, either price or review or availability needs to be present.

I used google's own example: http://support.google.com/webmasters/bin/answer.py?hl=en&answer=186036

I also tested the microformas.org: http://microformats.org/wiki/google-rich-snippets-examples