The Gevey SIM allows you to unlock your iPhone without the need of a jailbreak. The SIM card force activates the iPhone’s baseband by exploiting the emergency dialer function.

Apple released iOS 5 Beta 2 last night, and it appears that the Gevey SIM is now blocked from working in this second iOS build. It’s suspected that Gevey will try to battle Apple’s patching of its interposer while iOS 5 is still in the beta testing stages. 

MuscleNerd confirmed on Twitter that the Gevey is indeed blocked in iOS Beta 2, after numerous tips and reports surfaced about the issue. Apple most likely received pressure from carriers to block Gevey’s exploit.

It’s assumed that Gevey will aggressively update its unlock while it still can. For now, iPhone 4 users with a preserved baseband who want an unlock with the Gevey SIM will need to stay on iOS 4, or remain on iOS 5 Beta 1.

For more information about iOS 5 Beta 2, check out our extensive roundup. Let us know about your experience with the Gevey SIM on iOS 5 in the comments below!

[Redmond Pie]