We are having the same issue here. When trying to connect to a SQL 2005 SSIS instance via SQL 2008 SSMS, the following error occurs. I have not been able to find any resolution for this:

TITLE: Connect to Server

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Cannot connect to .

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ADDITIONAL INFORMATION:

Failed to retrieve data for this request. (Microsoft.SqlServer.Management.Sdk.Sfc)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&LinkId=20476

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Connect to SSIS Service on machine " " failed:

Class not registered

.

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Connect to SSIS Service on machine " " failed:

Class not registered

.

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BUTTONS:

OK

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