DALLAS ( TheStreet) -- AT&T ( T - Get Report) investors expecting a massive boost from Apple's ( AAPL - Get Report) new iPhone 4 are likely to be disappointed when the telecom giant reports its second-quarter numbers Thursday morning.

Apple and AT&T are experiencing phenomenal demand for the new iPhone, but the telco is unlikely to see the true upside until later this year, according to analysts.
AT&T

"Based on the late-June launch of the iPhone 4, we expect minimal impact on AT&T's second-quarter net adds," wrote Brett Feldman, a research analyst at Deutsche Bank, in a note released earlier this week. "However, a full quarter of iPhone 4 sales and other product launches should drive improved post-paid trends in the third quarter."

For this quarter, Feldman said that the iPhone 4 could help drive an estimated 550,000 post-paid net adds for AT&T. For the third quarter, the analyst is forecasting 900,000 post-paid net adds.

Like Apple, AT&T has struggled to cope with demand for the iPhone 4. The device continues to fly off the shelves, despite Apple's Antennagate nightmare. Apple's CEO recently announced that more than 3 million of the new iPhones have been sold, and the iPhone 4 has easily surpassed initial demand for the popular iPhone 3GS.

Investors, though, have been underwhelmed by AT&T. Currently trading at $24.83, the Texan telco is close to its 52-week low of $23.78, and the company's stock has dipped more than 11% this year.

Investors looking for a major revenue hike when AT&T announces its results on Thursday are also likely to be disappointed. Analysts surveyed by Thomson Reuters expect AT&T to post second-quarter revenue of $30.9 billion and earnings of 57 cents a share, compared to sales of $30.7 billion and earnings of 54 cents a share in the prior year's quarter.

One bright spot: Recent years have shown that AT&T's shares rise immediately after the telco releases its results. Over the past five years, the company's stock has returned an average of 1.9% on the day of its second-quarter results.

AT&T can also count on its deal to sell Apple's iPad to boost its second-quarter revenue, and investors will also be keen to hear more about a healthier spending climate in corporate America.

During its first-quarter results, AT&T discussed "encouraging signs" for enterprise spending, although at least one analyst thinks that the telco may downplay this trend when it releases its second-quarter numbers.

"Recent macro data points and concerns regarding the trajectory of the nascent recovery increase the possibility of more muted commentary," explained David Barden, an analyst at Bank of America/Merrill Lynch, in a note released on Wednesday. Barden projects a "marginal improvement" in AT&T's year-over-year enterprise revenue decline from 5.4% in the first quarter to 5.1% this quarter.

-- Reported by James Rogers in New York

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