We have recently seen that Apple had deposited a new patent to control our iDevices in case of fraudulent use : it means if your iDevice is jailbroken or not !
You can also note that several users has reported that some apps like Mon Budget du Credit Agricole on the AppStore detects if your iDevice is jailbroken.
Chpwn, member of the Dev Team has said that a new jailbreak (for iOS 4.1 ?), they could disable this kind of spywares.

• I remind you that in September, the new iOS 4.1 will be released, with the integration of the Game Center and an improvement of the iOS for a better compatibility on iPhone 3G which suffers of solwness with the actual iOS 4x.
• Golden rule : Go far far away from an update from iTunes or a new iOS when you're jailbroken !!

This jailbreak table should help you. Find your device and your firmware and click the links in the box for the jailbreak software and guides that should work for you. Note that RED means not yet done. GREEN means is done and working. No color change means that the jailbreak works, but may not be optimal or may not work in all cases. The guides should have more details. The green is the recommended solution for you.

Firmwares* iPod FW iPhone FW	iPhone 4	iPhone 3GS	iPhone 3G	iPhone 2G	iPad	iPod 3rd Gen	iPod 2nd Gen
4.0.2	Not Yet	Not Yet	Redsn0w 0.9.5b5-3 or newer Unlocked	Does Not Exist	Does Not Exist	Not Yet	Not Yet
4.2.1	Green Poison RC5 or Newer, no unlock	Green Poison RC5 or Newer, no unlock great for older bootrom , unlock with redsn0w / ultrasn0w.	Redsn0w 0.9.6b4 or newer, unlock with redsn0w / ultrasn0w	Does Not Exist	GreenPois0n RC5or newer	GreenPois0n RC5or newer	GreenPois0n RC5or newer
4.0.2-4.1	Green Pois0n (4.1 only) or Limera1n	Green Pois0n (4.1 only) or Limera1n	Redsn0w 0.9.6b1 or newer No unlock yet.	Does Not Exist	Does Not Exist	Green Pois0n (4.1 only) or Limera1n	Redsn0w 0.9.6b1 or newer MC models, use ipod touch 3g instructions
4.0-4.0.1	Jailbroken - Jailbreakme 2	Jailbroken - Jailbreakme 2 JB with stipulations: 1) Must already be pwned 2) Unofficial pwnage only Download here, use pwnage guide for help. Or use premade custom 4.0.1 firmware (google it). Recommend wait for official version. Unlocked	Jailbroken - Jailbreakme 2 Unlocked	Does Not Exist	Does Not Exist. See 3.2.1	Jailbroken - Jailbreakme 2	Jailbroken - Jailbreakme 2
3.2-3.2.1	Does Not Exist	Does Not Exist	Does Not Exist	Does Not Exist	Jailbroken - Jailbreakme 2	Does Not Exist	Does Not Exist
3.1.3	Does Not Exist	Jailbroken - Spirit / Redsn0w v0.9.4 / Pwnage Unlocked	Jailbroken + Unlocked - Spirit / Redsn0w v0.9.4 / Pwnage	Jailbroken + Unlocked - Spirit / Redsn0w v0.9.4 / Pwnage	Does Not Exist	Jailbroken - Spirit	Jailbroken - Spirit
3.1.2	Does Not Exist	Jailbroken + Unlocked - Spirit / Redsn0w v0.9.4 / Pwnage / Blackra1n	Jailbroken + Unlocked - Spirit / Redsn0w v0.9.4 / Pwnage / Blackra1n	Jailbroken + Unlocked - Spirit / Redsn0w v0.9.4 / Pwnage / Blackra1n	Does Not Exist	Jailbroken - Spirit / Redsn0w v0.9.4 / Blackra1n	Jailbroken - Spirit / Redsn0w v0.9.4 / Pwnage / Blackra1n
3.1	Does Not Exist	Jailbroken + Unlocked  / Pwnage	Jailbroken + Unlocked / Pwnage	Jailbroken + Unlocked / Pwnage	Does Not Exist	Jailbroken / Pwnage	Jailbroken / Pwnage
3.0.1	Does Not Exist	Jailbroken + Unlocked - Redsn0w v0.8 / Pwnage	Jailbroken + Unlocked - Redsn0w v0.8 / Pwnage	Jailbroken + Unlocked - Redsn0w v0.8 / Pwnage	Does Not Exist	Jailbroken - Redsn0w v0.8	Jailbroken - Redsn0w v0.8 / Pwnage
3.0	Does Not Exist	Jailbroken + Unlocked - Redsn0w v0.8 / Pwnage	Jailbroken + Unlocked - Redsn0w v0.8 / Pwnage	Jailbroken + Unlocked - Redsn0w v0.8 / Pwnage	Does Not Exist	Jailbroken - Redsn0w v0.8	Jailbroken - Redsn0w v0.8 / Pwnage
2.2.1	Does Not Exist	Does Not Exist	Jailbroken + Unlocked - Quickpwn / Pwnage	Jailbroken + Unlocked - Quickpwn / Pwnage	Does Not Exist	Does Not Exist	Jailbroken - Obsolete. Update

Download 4.0 : Official

MakeItMine is a free tweak available on ModMyi.
This tweak will permit you to customize in one shot the name of your carrier or replace the time in your Statusbar by a custom name!

Repo : ModMyi.
Version : 4.0
Autor : Eric Sadun.
Compability : OS x3,iOS 4x,iPhone 4.
Dependancy : None.
Price : free.

• Carrier : change the nom of your carrier or iPod.
• Banner : change the nom where you can read the time.
• Let the space empty to go back to default text, apply and respring.

Notes :

• Installation

Download 1.1 : Official

Six Icon Dock is a free tweak available on ZodTTD.
This tweak like Five Icon Dock, will permit you to have 6 icons in the dock of your Springboard.
Requires to uninstall Five Icon Dock if you have it!

Repo : ZodTTD.
Version : 1.1
Autor : Gi-lo.
Compability : OS x3,iOS 4x
Dependancy : iconSupport 1.6.4.
Price : free.

Notes :

• Installation

Download 1.1-1 : Official

Get five icons in your multitasking switche.
 


Notes :

• Installation

Download 1.0 : Official

B-Cards is a new application available on BigBoss.
This application will permit you to easily create a visit card that you can send by Mail or MMS.

Repo : BigBoss.
Version : 1.0
Autor : CApp Factory.
Compability : OS x3,iOS 4x,iPhone4.
Dependancy : Aucune.
Price : free.

Notes :

• Installation

Download 1.6 : Official

Before called Advanced Preferences, Xtreme Preference will permit you to add many features of settings. An excellent alternative to Supreme preference.

Repo : Cvseuy.com.
Version : 1.6
Autor : CSDev.
Compability : iOS 4x.
Dependancy : Repository Icons Cvseuy, WebView Controler.
Price : free.

Notes :

• Installation

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Previous Version
1.3 beta : 4shared

Download 1.0 : Official

WeatherFurikIOS4 is a free theme available on ModMyi.
A meteo widget for your SpringBoard.
Compatible iOS 4x.
Requires WinterBoard and iBlank.

Repo : ModMyi.
Version : 1..0
Autor : bahtiar.
Compability : iOS 4x.
Dependancy : WinterBoard.
Price : free.

Notes :

• Installation