Australian share trading ground to a halt mid-session, and failed to reopen before the market close, due to a glitch on the Australian Securities Exchange.

Trading was suspended for all stocks at 2:48pm (AEDT) due to the failure of the exchange's computer system to send confirmation messages for trades in some companies.

The ASX had been hoping to get the system back up and running for a special after-hours trading session, however the exchange's technicians could not resolve the problem this afternoon, and there will be no further trading today.

The ASX's spokesman Matthew Gibbs says all trades processed before the market went off-line will stand and are unaffected by the suspension of trade.

He says normal clearing is now taking place, and the closing price of shares will be the price they were at when trading was suspended.

Mr Gibbs says the whole market had to be shut down to fix the problem, even though the original glitch only affected some companies.

He says the exchange's technicians are still working on the problem.

"We are working towards having the market up and running as normal tomorrow morning," he told ABC News Online.

A trader at IG Markets Chris Weston says the stock exchange did the right thing by suspending all trade, even though the glitch only affected some companies.

"You could actually see your trades going through, but it actually wasn't reporting it back to the market," he told ABC News.

"So, as a disclosure situation, the ASX did the right thing in closing the market whilst they do the probe."

He says the outage highlights the need for other exchanges to be opened to compete with the ASX.

"If we had multiple exchanges, for example Chi-X, people would then be able to look at the alternative exchange and actually be able to trade on the alternative platform if the primary exchange is down," he explained.

"In London, the FTSE, on Friday traders weren't able to trade on the primary exchange, but they were able to trade on the alternative platforms, of which there are a few, and that situation was avoided."