Biztalk Server Reference In VB.NET

hi
i want to set a ManagementEventWatcher for Biztalk Suspended Queue
Document created as soon as any document will be kept in suspended
queue my applicaion would recieve event so that i can take further
actions on it
i am using pretty simple method
Try
Dim ms As New
System.Management.ManagementScope("root\MicrosoftBizTalkServer")
w = New System.Management.ManagementEventWatcher(ms, New
System.Management.EventQuery("Select * from
cs_SuspendedQErrorStrings"))

w.Start()
Catch ex As Exception
MsgBox(ex.ToString)
End Try

thats it..
my code but it is giving me an exception of "Invalid Namespace"

thanx in advance