This issue is being currently faced by users in my company as well. And I got the same response from MSFT.

Janakiram MP explains us why “Send To Email” feature is not working with Outlook 2010. Our environment is as follows:

1. Windows Server 2008 R2 64 Bit.
2. Office 2010 64 Bit.
3. Microsoft Dynamics GP2010 SP1.

Anyone facing this issue with above configuration may just want to confirm that it’s not possible at all with 64 Bit Office 2010.

VAIDY