X-Ray Mail Assistant 

X-Ray Mail Assistant is an email header filter and POP/SMTP server switching tool. It runs as a local POP/SMTP relay server and scans your incoming and/or outgoing mail.
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SmartSerialMail 

SmartSerialMail allows to send e-mails automatically to a large number of recipients. E-mails can be sent using MAPI or SMTP and up to 64 threads may be used, which allows an optimal usage of your internet connection.
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GFI MailEssentials for Exchange/SMTP 

Spam protection and email management at server level. GFI MailEssentials offers a fast set-up and a high spam detection rate using Bayesian analysis and other methods - no configuration required. Also adds key email tools to your mail server.
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