The import delay seems to stem from a U.S. International Trade Commission case that Apple won last December, against HTC. Then, the ITC ruled that several of HTC's handsets infringed upon a pair of Apple patents, with the ruling included a ban on the importation of infringing devices starting in April.
However, HTC quickly responded to the ruling, saying say that it had already designed a workaround for the issue in question. That said, the ban went into effect on April 19, and U.S. Customs is now examining these devices to see if the patent issues at hand have been corrected.
"The US availability of the HTC One X and HTC EVO 4G LTE has been delayed due to a standard U.S. Customs review of shipments that is required after an ITC exclusion order. We believe we are in compliance with the ruling and HTC is working closely with Customs to secure approval. The HTC One X and HTC Evo 4G LTE have been received enthusiastically by customers and we appreciate their patience as we work to get these products into their hands as soon as possible."
The customs delay is affecting supply of AT&T's HTC One X, which is out of stock online and is in short supply or out of stock in retail stores, as well.
Meanwhile, the EVO 4G LTE was scheduled to launch on May 18, but Sprint has now halted pre-orders on its site and the Wall Street Journal said that the launch has now been delayed because of the customs issue.