The partnership is based on a variety of new and existing products, including Microsoft Office Live Meeting and Live Communications Server 2005, its enterprise instant-messaging and presence-enabling platform.
Office Live Meeting is the company's web conferencing service, which provides a way for staff to participate in interactive meetings and share documents via the internet.
The partnership will also support the newest addition to Microsoft Office - code-named Istanbul - an integrated communications client that provides real-time collaboration.
Designed as the preferred client for Live Communications Server 2005, Istanbul will bring instant messaging, presence capabilities, PC-based voice and video and telephony integration to a single desktop, the company said.
The main Siemens technology involved in the agreement is Hipath Openscape, a presence-enabled collaboration portal built on Live Communications Server 2005 and Istanbul.
The portal allows users to discover where other users are and what functionality they have available on the access device they are using.
Openscape is designed to improve enterprise connectivity, with both device and user presence controls across multiple media and devices, including instant messaging, e-mail, work phone, mobile phone or home phone.
"The alliance demonstrates forward thinking by each company about the future of converged voice and data leadership," said Brent Kelly, an analyst at Wainhouse Research.
Kelly said linking Live Communications Server with voice and presence collaboration and existing workflow tools would benefit users preparing to move to next-generation voice over IP products.