Early this morning, we posted a video showing FaceTime on jailbroken iPhone 3GS running iOS 4.1. The folks behind the project has uploaded the tweak to enable iPhone 4-only FaceTime video calling option on iOS 4.1 for iPhone 3GS users.
Here's a quick video to watch it in action:
The tweak is available in Cydia for free. To enjoy using the tweak, you have to jailbreak your iPhone 3GS using Limera1n then tap on Cydia, touch Manage then choose Sources and add http://apps.iphoneislam.com. Now, search for FaceIt-3GS and install it. Once installed, navigate to the Settings app and activate FaceTime as shown in the screenshot below and wait for some minutes till it complete the process.
So, after you try it, tell us how does it work with you in the comment section below.