Portal Logout redirects to startPage of Server instead of /irj

hello all

we currently have an issue with the Portal system where the logoff redirects the user to the startPage of the Server instead of /irj

When the user logoff, it goes to https://server:port/startPage

The UME Redirect property is mentioned as /irj/portal

On logoff, the url called is https://server:port/irj/servlet/prt/portal/prtroot/com.sap.portal.navigation.masthead.LogOutComponent

It calls the standard logout component, and it has not been modifed.

Any pointers why the logoff would redirect to startPage instead of /irj

Thanks

Sandip