Unison Technologies, with an assist from Canonical and Ubuntu Linux, says it is “launching a major threat to Microsoft Exchange.” Hmmm. The VAR Guy has heard similar grandstanding before from a range of companies. But Unison has caught our resident blogger’s attention a few times. Here’s why.

Unison ranks among the few unified communications companies that has embraced Ubuntu — Canonical‘s fast-growing Linux distribution. In its latest attack against Microsoft, Unison is now launching a “free, sponsor-supported unified communications platform.”

Huh? Does that mean users will need to listen to commercials between phone calls? Actually, The VAR Guy has to concede: He’s not sure how the “free” offer works. Travel delays have prevented our resident blogger from speaking with Unison directly.

But here’s what The VAR Guy has heard so far:

Of course, The VAR Guy does have to offer Microsoft and Cisco some equal time here. Scrappy start-ups have attempted to knock off Microsoft Exchange for more than a decade. But we’ve all seen the corporate email market share figures: Exchange still dominates. And companies that attempt to disrupt Cisco often short circuit somewhere along the way. Oh, and we all know how software companies that promote “free” solutions often struggle to generate profits.

Still, Unison is declaring war against the unified communications establishment. The VAR Guy will be watching to see if solutions providers join the cause.

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