Someone finally apologized for the mess Apple and its carrier partners made of the iPhone 4 pre-order process Tuesday.

In statement released Wednesday, Apple (AAPL) announced that the number of pre-orders it took — more than 600,000 — was a one-day record. It was also more than it or its partners were prepared to handle, and for that it issued a formal apology “to everyone who encountered difficulties.”

In the five countries where Apple began taking orders for the new iPhone 4 Tuesday there were widespread reports of delays, system malfunctions, server breakdowns and even security breaches that switched credit card numbers and exposed users’ personal information.

In the U.S., AT&T (T) finally suspended pre-orders while a special team worked by hand through the orders that piled up the day before. According to AT&T, its pre-order sales Tuesday were ten-times higher than last year’s iPhone 3GS pre-orders.

Wall Street rewarded Apple for the pre-orders it managed to take on Tuesday. Shares closed at 267.25, up $7.56 (2.91%) for the day.

Below: Apple’s statement.

Yesterday Apple and its carrier partners took pre-orders for more than 600,000 of Apple’s new iPhone 4. It was the largest number of pre-orders Apple has ever taken in a single day and was far higher than we anticipated, resulting in many order and approval system malfunctions. Many customers were turned away or abandoned the process in frustration. We apologize to everyone who encountered difficulties, and hope that they will try again or visit an Apple or carrier store once the iPhone 4 is in stock.

See also:

• iPhone 4 stampede tramples AT&T
• How many iPhones did Apple just sell?
• Apple Store app crashes on launch
• iPhone 4 (not) available for pre-order
• Japan avoids an iPhone 4 meltdown

[Follow Philip Elmer-DeWitt on Twitter @philiped]