The stock market party at Research In Motion ( RIMM) may be winding down, but it is not over yet.

News of Apple's ( AAPL) iPhone dealt the handheld-device maker's shares a blow that it may find difficult to recover from, say some fund managers.

But the impending release of two new models, code-named Indigo and Crimson, could boost the stock, at least in the short term.

Since Apple announced the iPhone on Jan. 9, RIM stock has been down nearly 11% since coming off a 52-week high of $142.16.

The release of Indigo and Crimson, upcoming versions of the BlackBerry 8800 expected to launch in February and May, respectively, could create a buzz around RIM and re-engage investors.

That, at best, could spark a short rally, says Robert Lawton, portfolio manager for the Catoosa fund, which is short on RIM. "The Pearl was thought to be more of a game-changer than Indigo will be," he says.

RIM closed down 3.92%, or $5.21, to $127.71 Tuesday. The stock is far off the 12-month target of $175 set by American Technology Research or $185 set by Goldman Sachs.

The key question now is: Can RIM recover to scale new heights, or has the stock had its run?

News of the iPhone has clearly jolted many investors, and RIM clearly has lost some of its luster. Investors are now likely to flock to Apple instead of RIM, say fund managers.

Apple and RIM are playing in different market segments, and Apple's iPhone is not a "real threat" to RIM's core business, which is the corporate market, says Romeo Dator, a portfolio manager with U.S. Global Investors, which owns shares of Apple but not of RIM.

Apple's iPhone targets consumers, something that RIM has just started with its Pearl device.

But RIM's recent run hasn't been about fundamentals. Much of the excitement around the company's stock has been Pearl, which was launched on Sept. 7 and made available to consumers through T-Mobile the following week.

Shares of RIM have been up nearly 63% since then. RIM now trades at nearly 28 times forward P/E, compared with traditional handset makers such as Motorola ( MOT), which trades at a P/E of 15, and Nokia ( NOK), which has a P/E of about 14.

"The fundamentals don't support it, and the stock is overvalued," says Lawton.

RIM could recover -- but only if investor sentiment around the iPhone turns negative, says Dator.

"It may take some sort of setback for iPhone for investors to rethink how successful Apple will be in the near term," he says.

Still, analysts such as Rob Sanderson of American Technology Research remain optimistic. The iPhone, concedes Sanderson, has been a downward catalyst, but he says that RIM has some aces left.

"They are hitting the sweet spot of product cycle for Pearl, and we think they have a bigger-selling proposition with Indigo," says Sanderson. American Technology Research does not own shares or have an investment banking relationship with RIM.