Updated from 3:27 p.m. EDT

Cingular's plan to slash spending confirms an unwelcome trend for suppliers.

The integration of AT&T Wireless' network is nearly done, and with its 90-city expansion goal for 3G service called universal mobile telecommunications systems, or UMTS, in sight, Cingular is expected to cut spending by $1.5 billion, or 20%, next year, say Lehman Brothers' analysts in a note Thursday.

By Lehman's estimates, Cingular's 20% cut would represent about 5% of total wireless spending in the U.S. next year.

Cingular is jointly owned by AT&T ( T) and BellSouth ( BLS). And for the telco's investors, the idea of a cost clampdown means better cash flow and higher earnings.

But for shareowners of wireless infrastructure outfits such as Powerwave ( PWAV), Ericsson ( ERICY) and Lucent ( LU), the news that a big customer will spend less next year fits an all-too-familiar pattern.

"This isn't really a surprise," says one hedge fund manager. "We saw what happened to Powerwave in the first quarter after Cingular made its cuts." In April, Powerwave warned of a 20% sales shortfall due to order cancellations by Cingular.

Powerwave is already down nearly 50% from March, when it hit its high for the year. "I'm pretty sure the price reflects what's going on, but this brings visibility into 2007 a lot closer," says the hedge fund manager.

A Cingular representative said next year's budget hasn't been released so he couldn't comment on the Lehman report. Cingular has about 18 cities and surrounding suburbs covered by the UMTS network. The goal is to have nearly 100 communities blanketed with the faster wireless data service by year end. Though not yet officially announced, Cingular turned on the UMTS service in New York on June 21.

Cingular is running a distant third place in a three-way wireless broadband race with Verizon Wireless, which is co-owned by Verizon ( VZ) and Vodafone ( VOD), and Sprint ( S). Cingular's UMTS, like Verizon and Sprint's evolution data-only, or EV-DO, technology, is designed to offer users mobile Internet connections at relatively fast speeds. But the service is expensive, around $80 a month, and aimed primarily at laptop-carrying business customers.

Lehman's analysts say that Cingular's UMTS network is "fairly empty" at this stage and that it would make sense if the spending moved away from expansion and toward promotion and sales.

Industry watchers say it may be too early to judge the success or failure of Cingular's UMTS effort.

"As more enterprise users take the service, you'll see it become more ubiquitous," says one person close to Cingular's UMTS plan. "And as the number of customers goes up, the price will come down. That just how these things work."

Ericsson and Lucent share the UMTS supply contract with Cingular and are the most vulnerable should Cingular stop expansion next year. But as the Lehman analysts note, continued upgrades by Verizon Wireless and Sprint could help offset the drain on Lucent.

Shares of Lucent, which is in a pending buyout deal with Alcatel, rose 2 cents to $2.40. AT&T was up 2 cents to $27.58, and BellSouth jumped a dime to $36.29 in afternoon trading Thursday.