New 2.5.1 install with Month and name permalink structure; Site works perfectly with all permalinks correct. However when using plugins that get permalink address like latest comments and popularity contest, I see permalinks that shows http://myzerowaste.com/1970/01/ in the sidebar in latest comments etc. This goes nowhere, although the actual post URI is correct and shows its correct permalink when it is called. This rogue URL appears only when certain plugins are used.
We've checked the plugins are working correctly and this appears to be WP problem. I've found nothing on google, so really hoping someone here might have an idea, please.