CallManager 3.3(3)SR3 cluster. One publisher and one subscriber. When you browse to the publisher <servername>/ccmadmin there are no problems accessing configuration details. When you attempt to browse to the subscriber <servername/ccmadmin the request fails and an HTTP error appears on the browser.
There are no problems with replication between the servers and all phones are successfully registered to the subscriber server. There are no problems with call processing.