So far we have not identified any issues in the RadGrid related to the service pack version of the Sharepoint environment.
If you provide some more details on the error (full exception, stack trace etc.), the grid's markup and code-behind configuration and the exact steps when it happens we can try to provide additional suggestions for troubleshooting.
Either way the grid should support any version of Sharepoint 2010 including Service Pack 1 and 2. It seems like the issue may be more related to some differences in the setup of the development and production environment.
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