Virtuemart 1.1.6 r2584
Joomla Breadcrumb not working in 1.1.6, it is working in 1.1.5 so a commit must have broken this.
See link for Video
http://www.protechsystems.us/stuff/joomla/vm/vm116breadcrumb.htm
Ok, there was a known and intended modification in breadcrumbs, because people asked to remove "double" items in breadcrumbs when you have menu items that point directly to VM products / categories,
We should verify why it breaks also "normal" navigation.
I tested SVN 2603, strange result breadcrumb works except for Hammer, have added video. http://www.protechsystems.us/stuff/joomla/vm/vm116-breadcrumb.html
This is because you have a specific menu item for "Hammer". VM finds that and creates a different breadcrumb. This is intended behaviour.
Of course, we can talk a lot about how breadcrumbs should be handled in this case, and different VM users can have different opinions, but this is definitely not a bug.
I think we already have done a step forward in not having duplicated breadcrumbs items; unless other critical bugs are reported, this is not gonna be changed again before 1.1.6 release.
I see, thank you for clarification, I have never used menu to link to a product, always used VM_menu so it should be ok.