Israeli broadband solution provider Alvarion (Nasdaq: ALVR) kicked off a new operating profit trend in its fourth quarter by reporting $532,000 in operating income. On a GAAP basis, the company landed $4.1 million in net income, but this includes $3.6 million added in from discontinued operations. The company also secured quarterly revenue of $66.3 million, up 32% from the same period last year.

But investors proved very unkind to Alvarion following its release and conference call and sent the stock down 8% for the day. Even though the company emphasized that it sees no impact from a slowing U.S. economy, the company noted that it is hurt by the weak U.S. dollar compared with the Israeli shekel. Because of exchange-rate fluctuations and falling interest rates, the company expects to report non-GAAP earnings of $0.00 to $0.03 per share next quarter, below the $0.05 per share reported this quarter.

But other factors also likely weighed on the minds of investors. One was AT&T's (NYSE: T) press release that it will be pushing ahead with investments in a next-generation technology called LTE (for Long Term Evolution). WiMAX is seen as an outside competitor to LTE and other evolving cellular technologies meant to bring higher broadband wireless services to consumers.

Verizon Wireless -- a joint venture between Verizon Communications (NYSE: VZ) and Vodafone -- has hinted at embracing LTE as well, leaving struggling Sprint Nextel (NYSE: S) and Clearwire (Nasdaq: CLWR) as lonely operators championing WiMAX platforms in the U.S.

Regardless of questions of adoption in the U.S., though, Alvarion continues to benefit from foreign customers such as Vodafone (NYSE: VOD) and France Telecom (NYSE: FTE) building out WiMAX networks in some regions. This continued growth gives management confidence in a revenue target of $275 million to $300 million for 2008.

Even with a reduced share price, Alvarion's enterprise value is still about 1.5 times trailing-12-month sales. This and the uncertainty around future profits mean Alvarion is a more risky play compared with more established and diversified peers. Even with the risks, though, the stock is a compelling play on WiMAX -- if investors have patience and the stomach for volatility.

More Foolishness: