Group list exclusions for messaging

1. A method, comprising:

receiving a message including a recipient list specifying a list of recipients to receive the message, the recipient list including a name specifying a distribution list including a list of message recipients;

receiving an exclusion command at a Simple Mail Transfer Protocol (SMTP) server, the exclusion command being implemented as an extension to SMTP and including an exclusion list specifying a list of recipients to be excluded from receiving the message even if specified in the recipient list;

determining by the SMTP server that the distribution list includes a name specifying a second distribution list stored on a server other than the SMTP server;

providing an SMTP command from the SMTP server to the server hosting the second distribution list in need of resolution;

providing the exclusion command from the SMTP server to the server hosting the second distribution list in need of resolution; and

removing a recipient from the recipient list by the server hosting the second distribution list in response to the exclusion command, the removing including filtering recipients in the recipient list to exclude recipients also in the exclusion list.

2. The method of claim 1 , further comprising sending the message.

3. The method of claim 1 , wherein the recipient list includes at least one of a recipient name and a recipient address.

4. The method of claim 1 , wherein the exclusion list includes at least one of a name specifying a distribution list, a recipient name, and a recipient address.

5. The method of claim 1 , wherein identifying recipients in the recipient list comprises executing an EXPN command specified by Simple Mail Transfer Protocol (SMTP).

6. The method of claim 1 , wherein the message is an email message.

7. The method of claim 1 , further comprising:

determining whether the distribution list is hosted by a remote computing device;

providing an SMTP expansion command to the remote computing device hosting the distribution list; and

receiving an expansion of the list of recipients included in the distribution list from the remote computing device in response to the SMTP expansion command.

8. A non-transitory tangible computer readable medium comprising embodied computer executable instructions for:

receiving a message including a recipient list specifying a list of recipients to receive the message, the recipient list including a name specifying a distribution list including a list of message recipients;

receiving an exclusion command at a Simple Mail Transfer Protocol (SMTP) server, the exclusion command being implemented as an extension to SMTP and including an exclusion list specifying a list of recipients to be excluded from receiving the message even if specified in the recipient list;

determining by the SMTP server that the distribution list includes a name specifying a second distribution list stored on a server other than the SMTP server;

providing an SMTP command from the SMTP server to the server hosting the second distribution list in need of resolution;

providing the exclusion command from the SMTP server to the server hosting the second distribution list in need of resolution; and

removing a recipient from the recipient list by the server hosting the second distribution list in response to the exclusion command, the removing including filtering recipients in the recipient list to exclude recipients also in the exclusion list.

9. The medium of claim 8 , further comprising instructions for sending the message.

10. The medium of claim 8 , wherein the recipient list includes at least one of a recipient name and a recipient address.

11. The medium of claim 8 , wherein the exclusion list includes at least one of a name specifying a distribution list, a recipient name, and a recipient address.

12. The medium of claim 8 , wherein the message is an email message.

13. The medium of claim 8 , wherein identifying recipients in the recipient list comprises executing an EXPN command specified by Simple Mail Transfer Protocol (SMTP).

14. A system, comprising:

a message including

a recipient list specifying a list of recipients to receive the message, the recipient list including a name specifying a distribution list including a list of message recipients;

a client computing device comprising computer software that includes instructions for providing a graphical user interface configured to

receive the recipient list in a recipient destination field displayed by the client computing device;

receive an exclusion list in an exclusion field displayed by the client computing device; and

send the message and the exclusion list to a server;

a first server comprising computer software that includes instructions for receiving the message from the client computing device;

receiving an exclusion command implemented as an extension to Simple Mail Transfer Protocol (SMTP) and including the exclusion list specifying a list of recipients to be excluded from receiving the message even if specified in the recipient list;

determining that the distribution list includes a name specifying a second distribution list stored on a server other than the first server;

providing an SMTP command to the server hosting the second distribution list in need of resolution; and

providing the exclusion command to the server hosting the second distribution list in need of resolution; and

a second server comprising computer software that includes instructions for:

receiving the SMTP command from the first server;

receiving the exclusion command from the first server;

removing a recipient from the recipient list if the recipient is included in the recipient list and the exclusion list, said removing comprising filtering recipients in the recipient list to exclude recipients also in the exclusion list responsive to the exclusion command t; and

sending the message according to the filtered recipient list.

15. The system of claim 14 , wherein the recipient list includes at least one of a recipient name and a recipient address.

16. The system of claim 14 , wherein the exclusion list includes at least one of a name specifying a distribution list, a recipient name, and a recipient address.

17. The system of claim 14 , wherein the software further comprises instructions for identifying recipients in the recipient list by executing an EXPN command specified by Simple Mail Transfer Protocol (SMTP).

18. The system of claim 14 , wherein the message is an email message.