Webcenter spaces pretty url not working after upgrading from 11.1.1.7.1 to 11.1.1.8.1

Webcenter spaces pretty url not working after upgrading from 11.1.1.7.1 to 11.1.1.8.1
Problem Description
---------------------------------------------------
1) We have our current system running in production (spaces) which is on webcenter 11.1.1.7.1 , we have upgraded our unit environment to 11.1.1.8.0 and applied patchset 11.1.1.8.1 .

1) In 11.1.1.8.1 upgrade as per documentation , pretty url syntax to go to the firt page/home page of any portal will be (http://host:port/webcenter/portal/SPACENAME/home) , however this syntax does not seem to work . All the subportals are navigating to the parent's portal home page following this syntax and we dont have any meta data where we can change this Url .

2) However we tried ((