The carrier also indicated advisories from at least one ISP on Friday that the problem was caused by a cable break were incorrect, with the outage instead being due to a problem with the so-called unprotected circuits used to supply some services.
iiNet and Internode had issued an outage alert to their customers on Friday, with the latter saying the fault was believed to be due to a cable cut in the US.
"We had an outage on Friday evening going through and it was rectified on Saturday morning," Southern Cross' director of sales and marketing Ross Pfeffer told ZDNet Australia in a brief telephone interview this morning.
The executive said the problem "wasn't a cable break or a fibre break or anything disastrous like that", but an issue had arisen within his company's premises in San Jose in the US.
Pfeffer said the problem affected a few of what he called "unprotected circuits", which are relatively simple point to point connections without redundancy sold by Southern Cross.
"If the circuit is disrupted in any way, then the customer hasn't got any other form of protection," he said.
"If you buy a protected circuit, your services are transmitted effectively over a loop. If one side of the loop breaks the other side's still there."
"It's really a customer decision as to whether they buy protected or unprotected capacity," he concluded.