Tag Archives: Proxy SIM

[Pre] Baseband Downgrade Tool For Rebel SIM Unlock

The proxy unlock seller of the Rebel SIM has just released a tool to downgrade the Palm Pre’s baseband to re-allow proxy SIM unlocking with their Rebel SIM. Find the manual here.

As we don’t have exact information about how the Rebel SIM works we suspect it’s based on the same background as the iPhone proxy SIM’s.

As there are serious security and legality implications concerning using proxy SIM unlocked devices on networks, you’d better stop by here to read what the iPhone Dev Team found out about proxy SIMs.

[Pre] UK’s O2 Palm Pre Unlocked using RebelSIM?

A video appeared showing that SIM locked Palm Pre’s from the UK seems to have been unlocked using a proxy SIM solution called RebelSIM. There is no further detailed information about if this is a safe unlock like with the proxy SIMs for the first gen iPhones or i RebelSIM cards use IMSI fake IDs.

In general we suppose to be cautious with proxy SIM solutions. Why? Basically it’s the same with the proxy SIM cards for iPhones (read here).

A software unlock – meaning a binary code modification of the baseband – is almost always the better solution from a technical point of view, but it on the way to being able to patch the baseband many other issues can occur.

So for people who are desperate for a Palm Pre: get yourself the german factory unlocked version and learn to live with a QWERTZ keyboard. It much less hassle imho.

[iPhone] iPhone 3G Unlock “yellowsn0w” on Distribution

… by the iPhone Dev Team. You guys really rock. The unlock tool requires a jailbroken iPhone 3G and either Cydia or the Installer installed to download the unlock program called “yellowsn0w” from the Dev Team’s repository.

The tool gets distributed for free. Anyway some code-thieves are obviously already selling it by saying it is their work. Find further information about yellowsn0w on the Dev Team’s blog.

And yes: happy new year guys. We’re back from vacation and Berlin is full of “white snow” :-))

[iPhone] Status Report for iPhone 3G Unlock Solutions


There have been rumors about circumventing that annoying SIM lock. As Geohot stated (read here), modifying the 3G baseband will not be an easy task. Because this task still needs to be solved, some guys thought bypassing simlock by using Proxy SIMs might be a good idea for 3G iPhones as well.

Differences between 2G and 3G iPhones

For 2G iPhones Proxy SIMs worked very good, because only the iPhone checked once at startup, if the SIM is from a supported country and carrier. SIM Proxys faked this first answer only and gave control back to the real SIM card, which has been asked for all details (IMSI, Country Code etc.) again. The then gotten details have been used to transfer to the network and to try to log in.

After investigating in the Proxy SIM possibilities for the 3G iPhone the iPhone Dev Team (namely: _ZF) stated that in contrast to the behaviour with 2G Proxy SIM solutions, the behaviour of 3G basebands is like transferring the first gotten IMSI code to the network. This means: for 3G iPhones the Proxy SIM will fake a test IMSI card and the iPhone will send this test IMSI code to the carrier to log in.

Legal and technical issues with 3G Proxy SIMs

Although applying methods like this in order to unlock the iPhone 3G is most likely illegal in many countries (because it violates contract), members of the Hackint0sh forum have played with Proxy SIMs on different networks in the world.

As expected the results are disappointing. Besides the questionable legal status of those operations there have been heavy technical problems.

  1. First being support for 3G. Currently no Proxy SIM supports it. You can only surf the net and check emails and so on using 2G/EDGE/GPRS technology – means same functions like with a 2G iPhone.
  2. Second being the problem of the IMSI fake ID. At least european carriers seem to have applied security precautions to their networks. After some time you will be logged out of the network. This may take some minutes to some hours.
  3. Third being the problem that people reported the Proxy SIMs are still too thick. Several people broke their trays when trying to release the tray from the iPhone.

Types and Brands of Proxy SIMs

Tested cards include:

Currently none of these Proxy SIMs work reliable (cf. iPhone Wiki). Our recommendation is simple: keep on waiting, the iPhone Dev Team will make it sooner or later. In case you cannot wait, get yourself a factory unlocked iPhone 3G from one of the countries supplying them (see country list here) and save precious life time.