Unified communications specialist ShoreTel (NASDAQ: SHOR) is shaking things up, management-wise, with Joe Vitalone returning to head up ShoreTel’s channel team as vice president of Channel Management. Tim Gaines will be taking the helm for North America Sales, while Mark Arman will lead International Sales and Worldwide Distribution.

Vitalone, who has held management positions at Siemens (NYSE: SI), AT&T Wireless (NYSE: T) and Wire One Technologies, rejoins ShoreTel after a stint at videoconferencing company LifeSize (now owned by Logitech), where he served as vice president of Sales for the Americas. Prior to joining LifeSize, Vitalone was a company officer and vice president for North America sales for ShoreTel from 2005-2009, where he managed the sales team through ShoreTel’s transition to a publicly held company.

Gaines joined ShoreTel in 2007 and now oversees North American sales for all on-premise solutions including unified communications, contact center and mobility. He previously served as regional director and general manager for a U.S. subsidiary of Fujitsu, where he developed and drove growth of the PBX switching systems business in the United States, and served as senior vice president of sales at Covad (now MegaPath), a provider of broadband and VoIP solutions for commercial and government business segments.

Arman joined ShoreTel in November 2006 and now leads ShoreTel’s international sales and worldwide distribution teams. From 2006 to 2012, he led ShoreTel’s business development efforts, including strategic planning, merger and acquisition, and global channel processes. Before joining ShoreTel, Arman was founding CEO of data management company WindSpring.

The executive changes are the latest in ShoreTel’s moves to gain more visibility and market share in the unified communications space. In January 2012 the company revamped its partner program to focus more on its relationship with resellers, and just weeks later acquired M5 Networks, adding hosted UC to its portfolio.

In late 2010 ShoreTel acquired Agito Networks to bolster its mobility prowess.