Exchange mailbox may have multiple SMTP addresses. For outgoing messages Exchange always uses the primary SMTP address. For example, John Doe has a mailbox with john.doe@comapnya.com primary SMTP address and john.doe@companyb.com secondary SMTP address. John Doe can easily receive the message addressed both to john.doe@comapnya.com and john.doe@comapnyb.com, but he can not send the message as john.doe@comapnyb.com because this behaviour is by design in Exchange server. ChooseFromOWA for Exchange 2003 application allows Outlook Web Access users to send message with any of their own SMTP addresses as the From address.
Full Specifications
What's new in version 1
General
ReleaseNovember 8, 2008
Date AddedApril 25, 2006
Version1
Operating Systems
Operating SystemsWindows
Additional RequirementsWindows 2003 Server, Microsoft Exchange 2003