I am wondering if anyone knows will the CRM2011 Customer Portal available in pinpoint
http://pinpoint.microsoft.com/en-us/applications/customer-portal-for-microsoft-dynamics-crm-2011-12884910826/reviews works with CRM4 On-Premises?
No, CRM2011 Customer Portal will not work on CRM4 . However, you can upgrade to CRM2011 and then install this Solution.
There was an older version of Customer Portal which might work for you on CRM4, You can try seeing/following up here
http://www.shanmcarthur.net/crm for it.