When it rains, it pours. And when the sun shines, you'd better wear sunscreen. You want a tan, not third-degree burns.

Mr. Market is certainly pouring sunshine on Sun Microsystems (NASDAQ:JAVA) today. The stock price has ballooned by more than 20% since Sun reported $3.2 billion of second-quarter sales and a GAAP net loss of $0.28 per share. For those keeping score at home, that's down from $3.6 billion in sales and a profit of $0.31 per share a year ago. And while the overnight pop should be welcome for current investors, let me remind you that Sun was trading higher than this sub-$5 level less than a month ago; it's lost 70% of its value over the past year.

In other words, put the champagne back on ice. This is not the magical turnaround you have been hoping for.

Me, I wanted to see some fresh thinking out of Sun's management. Instead, I only got the usual potpourri of "Wow, we can do benchmarks!" and "We're still releasing new products!" For example, you might think that Sun could make a move in the red-hot virtual server sector, based on its xVM virtualization platform. But the virtualization and software management division saw a 29% yearly slide in sales, while rival VMware (NYSE:VMW) reported a 25% year-over-year sales increase. That's one opportunity lost, or at least rapidly slipping through Sun's hot little hands.

The company keeps plugging on both the hardware and software sides of the house, as if Sun were a miniature IBM (NYSE:IBM) or Hewlett-Packard (NYSE:HPQ). That may have been true 10 years ago, when Solaris servers and Sparc chips were the envy of Silicon Valley, playing vital parts in the early years of the Internet.

But Sun lost a step somewhere. It became an also-ran, with flagging sales and a multiyear stock slide. Now, even little Linux veteran Red Hat (NYSE:RHT) can rival Sun's market cap, while HP, Dell (NASDAQ:DELL), and IBM are making mincemeat out of Sun's server share. Even Cisco (NASDAQ:CSCO) now wants a slice of that hardware pie. Get out while the getting's still decent, Sun.

My suggestion is simple: Split the old Sun into two businesses. Let one company figure out how to sell chips and servers, while the other gets a handle on turning a profit from open-source software. Hey, I've seen more radical splits than that lately. At least this one would actually make sense.

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Fool contributor Anders Bylund owns shares in ... well, none of the companies discussed here. You can check out Anders' holdings or a concise bio if you like. The Motley Fool is investors writing for investors.