Issue filter function "lastLogin()" doesn't work

This filter should show issues that are updated since last login:
issue in watchedIssues() AND updated >= lastLogin() ORDER BY updatedDate DESC

Since I log in every day (as in clicking the "Log in" button with user/pass saved by the browser), this filter should only have changes since yesterday's login. Instead it shows issues with "updated" dates going back to a month ago. (see image)

Our Jira domain is: jira.atlassian.teliasonera.net
My account there is probably irrelevant, but you can mail me for questions: robert.peetsalu@iglu.ee

I didn't find any duplicate issues. Here's a suggestion which resulted in the lastLogin() function being developed by Justus Pendleton:
https://jira.atlassian.com/browse/JRA-865