Links to a node are broken if a URL alias changes

If a node's URL alias changes, any pre-existing links to the node become broken. Here's a use case using two pages:
* page 1 (node/20) is created with a URL alias of /test
* page 2 (node/21) is created, and includes a link [node:20]

At this point, page 2 includes a link to page 1 using the URL /test. If page 1 is updated and its URL alias changed to /test2, the link on page 2 is broken, since it continues to use the URL /test2.

I think the problem is that the filter cache isn't getting cleared correctly in the link_node_nodeapi function. The code currently calls cache_clear_all(null, 'cache_filter'), which only clears entries that are currently allowed to expire. This should probably call cache_clear_all('*', 'cache_filter', TRUE) instead to force the entire cache to be cleared.