Text messages have been delayed for several hours after a faulty Vodafone computer server hung on to messages, rather than passing them on. Vodafone spokesman Paul Brislen said the problem, which began on Tuesday and affected texts between Vodafone, Telecom and 2degrees, caused a backlog until yesterday morning. Vodafone would not say how many texts had been delayed. Mobile phone users send tens of millions of texts every day. One irate customer said yesterday that a text message had been delayed nearly six hours. 2degrees spokeswoman Bryony Hilless said Vodafone notified it of the problem on Tuesday evening and it appeared to be resolved by 4.30am yesterday. David Stone, the head of industry body the Telecommunications Carriers Forum, said texting was not as reliable as making a voice call. It was a service that came about accidentally, did not use mobile phone companies' core systems, and it was a case of "buyer beware". Brislen said 99 per cent of texts between Vodafone customers were delivered promptly but messages could be held up for a variety of reasons, for example if either the sender or receiver was outside coverage or because of faults. Telecom head of messaging Jason Foden said congestion was also possible at busy times such as New Year's Eve. Spokeswoman Rebecca Ingram said 97 per cent of all texts, including those to other networks, were delivered within a minute. Brislen said people should not rely on texts in an emergency. "You can't rely on it as an emergency service. It is not rated at that level." Telecom mobile users have been quick to provide examples of jumbled text messages after a system glitch was highlighted by The Dominion Post. The problem came to light after Salvation Army church leader Steve Molen sent a message to wife Faye that, when received, had a new ending that appeared to disrespect Mrs Molen's mother. Other people have now come forward, including Julie Woollett, from Waikato, who said she received corrupted text messages from her daughter on three occasions. "The message she sent me had the remnants of another text message she sent to someone else days beforehand and the end of her original text to me was gone." Telecom sponsorship and Mobile PR manager Rebecca Ingram said there had been 20 reports of muddled texts in the past few months. An investigation is under way to find the cause.