Telecom rivals Telstra and Cable & Wireless Optus are duelling it out in federal court following allegations that Optus' latest advertising campaign is misleading.

Telstra has objected to Optus's claims that its mobile phone network has -doubled in size in the last two years", with the industry bigwig arguing that customers are likely to incorrectly interpret that to mean the network has doubled in -geographic size". -It hasn't come anywhere close to that," Telstra's Tim Scott told ZDNet Australia.

Justice Ryan ordered Optus to refrain from using that specific wording.

When contacted by ZDNet Australia, Optus was only too happy to -put a bit of reality back in the story", claiming the advertisement wording simply refers to its number of base stations and believes it has -touched a nerve" with Telstra.

-The pedantic court action by Telstra outlines a striking sensitivity by Telstra as Mobile Number Portability (MNP) looms," an Optus spokesperson told ZDNet Australia.

But when asked if Optus had touched a nerve, Telstra's Scott said: -it's the opposite."

-Optus is obviously concerned with the fact that it's deficient in terms of network coverage which has led them to make these claims."

Optus's backlash to this comment was that size isn't the issue, -it's reliability and quality".

Optus has dubbed Telstra's federal court action -litigation for litigation sake," considering the original advertisement that disgruntled Telstra was taken down on Friday due to the -natural evolution" of the campaign - a move Optus claims Telstra was aware of. -It's disappointing to have a battle of semantics and grammar," Optus's spokesperson said.

Telstra has hit back with the claim that Optus was -deploying delaying tactics" and described its competitor as being -belligerent about the whole thing".

-They left us no option but to go to court," said Scott.

However, Telstra has recently been put in the spotlight by its own customers, who claim the telco heavyweight misled them into broadband Internet access services by advertising them as -unlimited" download plans.

Telstra maintains, however, that it's under extremely close scrutiny from the ACCC -- -more so than our competitors".

The ACCC said it has "encouraged" Telstra to move away from its marketing claim of "unlimited download". "We saw a potential to mislead, at worst, or at least confuse customers," the ACCC's Lin Enright told ZDNet.

The Telecommunications Industry Ombudsman (TIO) said it receives complaints from people who believe they have been misled by marketing and advertising claims. Recently this has included claims about 'pre-paid' mobiles, 'unlimited' Internet downloads, 'free' time, and claims about high-speed Internet access.

"The TIO's view is that the terms and conditions attached to a product or service should not contradict the very meaning of the word or words used to sell the product. Complaints to both the TIO and the ACCC indicate that Australian consumers have a low tolerance for inaccurate marketing pitches."

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