Shares in C&W Optus, which is 52.8 per cent owned by Britain's Cable and Wireless Plc, ended their first day's trade at A$2.65, representing a 43-per cent premium to the retail price of A$1.85 in its initial public offering (IPO).

This was above market expectations for a listing price of about A$2.50 and put C&W Optus firmly into Australia's top 15 listed companies with a market capitalisation of A$9.21 billion.

"It's come on at a pretty strong price, there's no doubt about that," said Credit Suisse Asset Management investment manager Tim Ryan.

"It's a pretty hefty premium," said Eric Gale, a senior institutional dealer at Ord Minnett.

The successful debut also reinforced a sea change in the Australian market over the last two years which has seen the traditionally dominant resources sector overwhelmed by finance and telecommunication groups.

Ironically, C&W Optus' share market listing took place a year to the day after Australia's largest telecommunication group, the one-third privatised Telstra Corp, joined the market.

Telstra has been the Australian market's star over the last year, doubling its share price and posting a record Australian corporate annual profit of A$3.0 billion.

Optus appeared to fare better on its first day than Telstra, but analysts and fund managers doubted it could repeat the stellar performance of the dominant market player.

C&W Optus' 43 per cent premium outpaced Telstra's 37 per cent premium on its first day. C&W Optus' first day trading volume of 316 million or 9.0 per cent of its shares also topped Telstra's 295 million or 6.9 per cent.

"I think it's got a bit more upside from here, but not a lot," said Ryan of Optus' prospects.

"Telstra effectively doubled in 12 months and I don't think Optus will double over 12 months. Telstra we though was cheap 12 months ago and Optus is probably not as cheap."