1840877 - com.sap.portal.navigation.AliasService does not implement method: SAP EP issue

Portal logon page does not appear when SAP Netweaver Portal is accessed with url http(s)://<host>:<port>/irj/portal after new portal 7.30 installation or upgrade to 7.30, rather 500 Internal Server Error occurs.
The problem also might occur when Enterprise Portal is accessed using IP address as http(s)://<host_IP_Address>:<port>/irj/portal instead of hostname.

The following exception is logged to the defaultTrace file

500 Internal Server Error is returned for HTTP request [http://<host>:<port>/irj/portal]:
  component [gateway],
  web module [irj],
  application [sap.com/irj],
  DC name [sap.com/irj],
  CSN component[EP-PIN-PRT],
  problem categorization [com.sap.ASJ.web.000137],
  internal categorization [-506802080].

[EXCEPTION]
java.lang.AbstractMethodError: Class "com.sap.portal.navigation.AliasService" does not implement the requested method "containWebXmlAliases()Z" inherited from interface "com.sap.portal.navigation.IAliasHelper"

SAP Netweaver 7.3x

500, Error, Application error occurred during the request processing Production ABAP R/3 ERP SRM CRM ERP PPM SEM APO XI PI PORTAL Test development QA deployment  , KBA , EP-PIN-NAV , Navigation , Problem