Mark the database trustworthy, you are under an EXECUTE AS context:
http://msdn2.microsoft.com/en-us/library/ms188304.aspx
The issue is described in BOL here:
http://msdn2.microsoft.com/en-us/library/ms166102.aspx
For a solution that does not require turnin on the trustworthy bit, see this
blog article:
http://blogs.msdn.com/remusrusanu/archive/2006/03/07/545508.aspx

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HTH,
~ Remus Rusanu
SQL Service Broker
http://msdn2.microsoft.com/en-us/library/ms166043(en-US,SQL.90).aspx
> Hi
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> Pauli