'The jinx hit first at Dubai Airport, where I discovered I had stupidly left home without blocking international roaming on my iPhone5.

"The jinx hit first at Dubai Airport, where I discovered I had stupidly left home without blocking international roaming on my iPhone 5."

I bought a plastic flower the other day, and it died. I should have known my luck was out. The jinx hit first at Dubai Airport, where I discovered I had stupidly left home without blocking international roaming on my iPhone5. Then, next mistake, I also had not shut off iCloud syncing. Within seconds of the iPhone booting, I got a text from Telstra saying 20 megabytes of data had been downloaded, and another, a few seconds later, taking it past 40MB. Sick at heart (the heart of my wallet), I shut down the phone and imagined Telstra's tumbrels rumbling off with a serious chunk of my money.

Dubai Airport's wi-fi isn't great, so the phone grabbed the cellular signal as soon as I switched on, and held it while the data downloaded. I have no idea what was downloaded, but at $15.36 a megabyte, it cost me $803.50, taking my monthly Telstra bill to a numbing $1200.

But why $15.36 a megabyte? Does it really cost that much to move a megabyte between Dubai and Melbourne? Or did all the telcos in the world meet over flagons of Dom Perignon to think up some gotcha numbers?

Tim Webber, Telstra's director of business mobility, says Telstra has to negotiate individual roaming agreements with each of the 500 foreign carriers with which it connects. Many are monopolies. Russia, for example, has 13 carriers, each with sole access to a bit of mother Russia's geography. Similar leverage is exerted, more by small countries than major nations.

''It is very hard for us to negotiate [reasonable data prices] in some countries,'' Webber says. Australians, among the biggest mobile phone users in the world, are also big travellers, and, like ET, want to call home, especially in emergencies.

Webber says Telstra feels a duty to provide connection for its globetrotting customers. Prices are coming down as global roaming burgeons, but in the end they are dictated by the rates foreign telcos impose, plus administration and engineering costs in Australia.

But as I've said, there was a jinx on my back. When I got home a couple of days before Telstra's bill was due for payment, I rang customer service to ask for a week's extension while I moved some roubles from one bank to another to meet the $1200 invoice. After ''thinking'', Telstra agreed, but then hit me with a $15 late-payment fee! Even the banks have moderated such fees, but not Telstra. Sure I was late, but what about the extra time that had been granted?

And still the jinx had me in its sights. Shortly after settling the bill, my cable internet connection failed. Telstra said no outage had been reported. The problem must be in my house. It would send a technician - in three days. Three days without the internet! So what about compensation for loss of service? Nowt, said the call-centre lady. ''The internet is classed as a luxury.''

Who says? I asked. ''The government,'' she replied. ''All Telstra has to do is provide basic telephone service.''

So what was all that government guff about how essential the internet was, and how the $35 billion (more likely $90 billion) the NBN would cost was a vital investment in the nation's future? But not everyone lost. I paid Telstra to use my iPhone's Personal Hotspot for internet connection.

So had the jinx done enough? Not likely. Still working on my internet problem, Telstra technicians found corrosion on the cable in the street. Fixed in a flash.

But my modem was judged to be dicky, requiring replacement. But new modems must be registered, without which service cannot be resumed. It takes 24 hours. Why? I never discovered. But the jinx had a catch-22. Not knowing registration takes 24 hours, you might repeat your online application when nothing seems to have happened. I did, three times. Each repeat sent me to the back of the queue.

In the end, after initially getting nowhere with customer service, I connected with an operator who not only alerted Telstra engineering, which quickly sorted things, but also checked afterwards that all was finally well. Full marks.

But the jinx had a final (I hope) slash. A few days after I'd paid my bill, Telstra announced reduced global roaming charges. A $29 monthly data pack once delivered 20 megabytes. Now, it allows 100MB.

It's vastly cheaper to block global roaming before you leave home. Organise a data pack for your phone or buy a global SIM card here or overseas. I Skype from my iPad at one of the multitude of free wi-fi hotspots in Britain and the United States and I have a £30 prepaid phone bought in a supermarket in England. It's fine anywhere in Europe, but, sadly, not in Dubai.