1)   IGetMail 2.3
IGetMail works with your Microsoft Exchange email server to download incoming POP3 email from multiple remote servers. It supports individual and group/domain accounts. Uses dial-up networking and operates on a time/frequency schedule you define.

 2)   Native POP3 Connector 2.4.1
Native POP3 Connector offers a standard solution for the problem with receiving mail through the POP3 protocol for Microsoft Exchange Server 2000/2003 and Small Business Server 2000/2003. NPC is a standard solution for MS Exchange Server: Connector.