The permissions check fails when the page is being linked by 'id' rather than by space key and title (which became the default in 1.0.3)

This is fixed in the new 1.0.3 distribution, but people encountering this problem can patch their own Confluence installations by placing the attached AbstractPageAction.class into their Confluence installations at confluence/WEB-INF/classes/com/atlassian/confluence/pages/actions/ and restarting the server.