Hi Terry.
Please see my earlier post in this thread. For some reason, the name of the Authorization Manager changes with the vSphere 5. objects.
Here's the code I posted earlier.
$domain = "ourDomain"
$groupname = "ourGroup"
$svcgroup = $domain + "\" + $groupname
$folder = Get-Folder -Name "ha-folder-root"
$authMgr = Get-View "AuthorizationManager-ha-authmgr"
$perm = New-Object VMware.Vim.Permission
$perm.principal = $svcgroup
$perm.group = $true
$perm.propagate = $true
$perm.roleid = ($authMgr.RoleList | where{$_.Name -eq "Admin"}).RoleId
$authMgr.SetEntityPermissions(($folder | Get-View).MoRef, $perm)