Liferay Portlet & secure connection (https)


We use vadin as a portlet for Liferay.
Portlet is used in the internal part of the portal.
This part is accessible by default through https.
When you access a page with the portlet, I get a message about unsafe content pages.

How to solve this problem?
Thank you

Alfresco Professional Integration:

If you are using the default PortalDefaultWidgetset, see (It includes a Google Analytics component which tries to load the google analytics script from a http url)