Hi,
Are youi talking about Designer Workfows or Visual Studio ones? In the case of Designer, the out of the box activity for sending an e-mail doesn't allow yo to do that...in the case of a Visual Studio workflow, you could create a custom for with this functionality.
Regards
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Juan Carlos González Martín MVP de SharePoint Server
Director revista CompartiMOSS: http://www.gavd.net/servers/compartimoss/compartimoss_main.aspx
Blog: http://geeks.ms/blogs/ciin
Twitter: @jcgm1978
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