Sydney  - The steamy text message sent to the wrong mobile phone is the cyberage equivalent of lipstick on your collar or an embarrassingly unexpected bunch of flowers.

A report by Australia's biggest phone company has found that nowadays a quarter of those who discover infidelity do so through a text message.

In most cases, according to a survey of 1,200 Telstra customers, the give-away is suspicious behaviour - taking a mobile into the shower for instance. A stolen search of the call register and the game is up. In other cases it's just incompetence - a text received that should have gone to someone else.

"It's no surprise that cheaters can often be caught out via texting, given that an affair is usually secretive," market researcher Mark McCrindle said. "It's likely the majority of communication would be done by text, as answering phone calls may arouse their partner's suspicion."

But the big difference is that phone calls don't leave a trace. They are like a letter burned after reading. And with phones, if you haphazardly dial the wrong number and get through to the wrong party, you can simply hang up. With text messaging, as with email, there's always a potentially embarrassing audit trail.

The solution for safe texting during an affair is to do what spies do and adopt code words - and drop the emoticons. (dpa)