Does Google penalize 301 redirects from my naked domain?

Does Google Search and other search engines penalize 301 redirects from my naked domain to my regular domain? I need such redirect from example.com to www.example.com because Google App Engine does not support naked domains.开发者_Go百科 If possible, please provide answers with updated references. Thanks!

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No, you will not be penalised. Google actually recommends that you set a preferred domain:

Note: Once you've set your preferred domain, you may want to use a 301 redirect to redirect traffic from your non-preferred domain, so that other search engines and visitors know which version you prefer.

Source: http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=44231