112 overrides most locks on most handsets.

112 overrides the phone lock more reliably than 999 will. It will do so on ALL GSM handsets, even quite old ones.

It also overrides the PUK lock!

Ireland's 999 / 112 call rates seem pretty ridiculous. One problem we had over here was that Vodafone Ireland (eircell) chose "121" for voicemail access way back when the mobile phone first hit the market in the 1980s. The 999 / 112 call centres were getting thousands of calls from people trying to check their voicemail and misdialling!

For that reason, 121 was withdrawn (sometime in the early 2000s) and "171" for voicemail access was made a requirement for all networks, including fixed line operators, to keep things a little easier to understand.

Also, Comreg removed any other 'short codes' close to 112.

Yet, we still seem to have the most ridiculous number of calls per capita !

There's a proposal for a pan-EU non-urgent emergency number. That should help! E.g. for 'curtain twitchers' reporting 'suspicious activities' ... Or people who need urgent information about how to open a can of beans.

Does 112 also bypass mobile phone number lock?

With mobile phone number lock on I've still unintentionally dialled 999 when the phone was in a pocket.

Does 112 also override the mobile phone number lock in the same way? I'm reluctant to test it out and can't find any web pages that say either way...

Roaming, 112/999/911, etc.

US law requires telcos to facilitate 911 calls.

Emergency calls from payphones are free

Have an analog carphone from the 80's? If it can find an analog transceiver, it works for 911.

Stole a phone and used it to arrange crack cocaine transactions for three days before it was disconnected, now one of those crack deals took a bad turn and you need help from the boys in blue? It works for 911.

As for roaming in the US, I can't speak for other carriers, but my Sprint cell phone automatically connects to other networks. However, a warning dialog informing you that a roaming rate will be charged appears whenever you make or answer a call, giving you the option to cancel before this happens. I've never noticed an extra charge for receiving text messages or voicemail notifications while roaming, and I don't bother accessing the internet from my phone, although I imagine a similar warning dialog appears when attempting to connect.

I have taken my phone to Toronto, Ontario, Canada, where, alas, I did nothing but roam. Although it did little else aside from keeping me accurately apprised of the time, it was convenient to have it with me as a phonebook; while I was in Canada I purchased a pay-as-you-go cell phone, so that in combination with a phone card I could make fairly inexpensive calls home.