Zero discount showing on certain products on category browse page

[iskye81]

Some typically odd VM behaviour here. On certain category pages products are showing up with a zero discount - these products have no discount associated with them, as can be seen when clicking through to the product page, where their pricing displays normally. See for example the "Half Pint Pewter Water Jug" on this page http://www.glenster.com/Tableware.html, and then the entirety of the products in this category http://www.glenster.com/Tradition/Tartan-and-Plaid.html.

The behaviour is presumably not random, but I can find no common link between the affected products/categories in order to resolve it.

[jenkinhill]

Both price layouts look the same to me.