A minor dispute over a misplaced key which blew up into a public relations fiasco has reportedly ended with the resignation of the president of $10bn-a-year multinational tech company EMC's Chinese division.

The incident has underlined the dangers of private emails becoming public, and drawn attention to the cultural disconnect between foreign managers and local staff in China.

EMC declined to confirm or deny details of the case when contacted by vnunet.com.

According to Chinese media reports, the incident started when Loke Soon Choo, president of EMC China, returned to his office late one Friday evening in April to find himself locked out.

The Singaporean executive fired off a curt email to his secretary, who had already left the office.

"You locked me out of my office this evening because you assume I have my office key on my person. With immediate effect, you do not leave the office until you have checked with all the managers you support," Loke wrote, according to copies of the emails seen by vnunet.com.

The secretary, Rebecca Hu, emailed a blistering reply. "I locked the door because the office has been burgled in the past. Even though I'm your subordinate, please pay attention to politeness when you speak. This is the most basic human courtesy. You have your own keys. You forgot to bring them, but you still want to say it's someone else's fault," she wrote.

Hu copied her reply, along with Loke's original email, to all of EMC's staff in China. Someone copied the email to a friend outside the company, and during the next couple of weeks the email exchange was forwarded around other companies in China, apparently reaching thousands of people, some of whom posted it on online forums.

It became a cause of heated online debate, with some supporting Hu, but others accusing the secretary of being stubborn, irresponsible and unprofessional. Some of the attacks on EMC have nationalist overtones, as the firm, and Loke, are foreigners.

"Foreigners come to China to lord it over others, not to help China's economic development," said one forum participant. "They want to keep down our wages and give the profits to foreign executives and their headquarters."

Another pointed out that the boss had made the error of cc-ing several other staff on his original email to the secretary, thus turning a private reprimand into a public humiliation.