Microsoft is hardly ignoring the iPhone, according to Fortune on Tuesday. The Microsoft Mac Business Unit (MacBU) has the iPhone SDK and is eager to find out of there are business opportunities for Microsoft to develop iPhone software.

"It’s really important for us to understand what we can bring to the iPhone," said Tom Gibbons, Microsoft’s corporate vice president of Specialized Devices and Applications Group. "To the extent that Mac Office customers have functionality that they need in that environment, we’re actually in the process of trying to understand that now."

Of course, while Microsoft and Apple are rivals in many areas, the MacBU in Mountain View, Calif has been delivering software for Macs for over a decade. The MacBU exists because it makes good money for Microsoft, to the tune of US$350M in revenue per year with a profit estimated at $200M. That group has a lot of experience writing Mac software, so it was natural for them to explore the iPhone SDK.

"We do have experience with that environment, and that gives us confidence to be able to do something," Mr. Gibbons said. "The key question is, what is the value that we need to bring? We’re still getting comfortable with the SDK, right? It’s just come out. So we had a guess as to what feasibility would be like, now we’ll really get our head wrapped around that."

In addition, another Microsoft group, TellMe, sees opportunity in voice recognition software, an area that Microsoft has spent a lot of R&D dollars. "If the SDK supports these things," said Mike McCue, the TellMe general manager, "we’re absolutely going to get a version out there as soon as we can..."

That Microsoft is looking to make money from the iPhone may seem ironic, but making money from Apple hardware is merely something the MacBU has been doing for a very long time.