Links on tabs turned into /user/%/edit, /user/%/contact, node/%/edit, admin/structure/types/%/fields, etc. Also, the links on Administration Menu module have the same issue.

Here's what I did so far.

1. I've cleared all cache via Admin Menu -> Flush all cache, via Development -> Performance and via emptying MySQL cache_* tables. Didn't solve.

2. I noticed that tabs are themed by the menu_local_tasks() function. I traced the function to includes/menu.inc, where I found the following snippet, which makes me think it might be related to this function.

* For example, the ancestors of node/12345/edit are:
 * - node/12345/edit
 * - node/12345/%
 * - node/%/edit
 * - node/%/%
 * - node/12345
 * - node/%
 * - node

UPDATE: Where is '%', of the above URLs, being populated? I want to be able to trace it.