Breadcrumb question

Hi,

If I understand correctly, the category breadcrumbs that appear at the top of the page when product info page is displayed should show either:

1. the path by which you navigated to that product (ie there is a cPath variable in the URL)

OR

2. the path for the master category for the product

I am finding with my client's site that even if I change a product's master category, it is not reflected in the breadcrumb behavior (i.e. if I do a search for the product and click on it from the results thus no cPath).

I have checked in the database itself to be sure the master category really is being changed but I am baffled how the wrong category continues to appear.

Any ideas?

BTW, I am running v. 1.3.8a and the "wrong" category breadcrumbs are a category that the product is validly linked to but not the master category.

I did a little bit of testing and found the following:

If I add a new product under a particular category, the master category ID defaults to the category I selected. The breadcrumbs correctly show the master category ID.

If I now link the product to a second category and leave the master category as is, the breadcrumbs still correctly reflect the master category.

Now if I change the master category to the second category, the change IS NOT reflected in the breadcrumbs. The old master category still shows.

Only if I completely unlink the product from that original category, do the breadcrumbs show the second category.

So, there seems to be some confusion about how the breadcrumb is calculated in the absence of a cPath URL variable.

If anyone can shed light on why this is the case or how to correct it, I'd be grateful.