NPE while trying to add role to repository or organization unit via kie-config-cli with BRMS/BPMS 6.1

Issue

We are facing an exception while trying to add role to repository or organization unit via kie-config-cli:

>>Please enter command (type help to see available commands):
add-role-repo
>>Repository alias:repository1
>>Security roles (comma separated list):userrole1
Unhandled exception caught while executing command add-role-repo error: null
java.lang.NullPointerException
        at org.guvnor.structure.backend.repositories.RepositoryServiceImpl.addRole(RepositoryServiceImpl.java:226)
        at org.guvnor.structure.backend.repositories.RepositoryServiceImpl$Proxy$_$$_WeldClientProxy.addRole(RepositoryServiceImpl$Proxy$_$$_WeldClientProxy.java)
        at org.kie.config.cli.command.impl.AddRoleToRepositoryCliCommand.execute(AddRoleToRepositoryCliCommand.java:39)
        at org.kie.config.cli.CmdMain.main(CmdMain.java:97)