How to reproduce:
create some node (say node/5) with "test-node" url alias
create a link from other node in the form href="node/5", rendered output of the node shows the link as "http://example.com/test-node" - nice!
change "node/5"'s alias to say "test-node-changed"
go back to the second node and see the link still shows "http://example.com/test-node" (and now it lead to nowhere!)
Expected behavior: the rendered link in the second node changes to "http://example.com/test-node-changed"
So, the output was cached. To reset it I had to reset the drupal data cache.
Is it possible to workaround that?