SM51 list of SAP instance hows "localhost" instead of the name of the host.

Hi,

In our landscape we are facing an issues related with hostname. in SM51 transaction where we see the list of application servers,there is entry "localhost" instead of it's value which we see in hosts file (/etc/hosts).I want to add one important thing that SAP is on  virtual machines.From the OS level we can see the hostname and it's showing us the correct name.

Any clue would be appreciated.

Thanks,

Rakesh