I´ve found your great website a few days ago and gave your script a try but it doesn´t work. I´ve leave you a message with the error message in comments. But anyway: now I´ve updated PowerCLI to 5.1R2 and after executing your script I get the following output:
PowerCLI C:\scripts> Get-AlarmActionState -Entity VMTEST1 -Recurse:$false
Get-AlarmActionState : Die Argumenttransformation für den Parameter "Entity" kann nicht verarbeitet werden. Der Wert "VMTEST1" vom Typ "System.String" kann nicht in den Typ "VMware.VimAutomation.ViCore.Impl.V1.Inventory.InventoryItemImpl" konvertiert werden.
Bei Zeile:1 Zeichen:29
+ Get-AlarmActionState -Entity <<<< VMTEST1 -Recurse:$false
+ CategoryInfo : InvalidData: (:) [Get-AlarmActionState], ParameterBindin...mationException
+ FullyQualifiedErrorId : ParameterArgumentTransformationError,Get-AlarmActionState
Sorry for the german output - I can´t got an english output. Oh and: It´s Windows Powershell 2.0.