I faced the same problem. When trying to open the Cisco Unified Communications Sizing Tool (http://tools.cisco.com/cucst) and sign-in I am stuck in a loop where ...1) I am sent to a "Log in to your account" page (https://cloudsso.cisco.com/....). 2)...
The link is forbidden. I can't view the page. ("You are not authorized to access this page.Many pages on the community are accessible only to Cisco customers, partners or logged in entitled guests.")
From what I've read, the Page feature and the Intercom feature both override the Do Not Disturb feature. In other words, the page will be heard whether DND is enabled or disabled by the end user.