多台电脑使用同一个开发者账号

借此贴总结一下自己今天把一个证书放到两个机器上 的经历：
http://developer.apple.com/library/ios/#documentation/Xcode/Conceptual/iphone_development/128-Managing_Devices_and_Digital_Identities/devices_and_identities.html

首先就是按照下面说的：
When you request a certificate from the iPhone Provisioning Portal, a public/private key pair is generated. The public key is included in your certificate. The private key is stored in your keychain. With these items, Xcode code-signs the applications you build with it. If you need to use another computer to develop iOS applications, you must transfer these digital-identification items to the other computer. You can do this in the Xcode Organizer.

To export your digital-identification items to a secure file, follow these steps:

Open the Xcode Organizer.
In the IPHONE DEVELOPMENT group, select Developer Profile.
Click Export Developer Profile.
Name the file, select a location for it, enter a password to secure the file, and click Save.
Now, when you need to develop iOS applications on another computer, import your digital-identification items into it by performing these steps:

Copy the developer-profile archive to the second computer.
On the second computer, launch Xcode.
Open the Organizer.
In the IPHONE DEVELOPMENT group, select Developer Profile.
Click Import Developer Profile.
Locate the archive, enter the password used to secure it, and click Open.

关键的一点就是不是直接从keychain里导出.cer文件，而是利用Xcode的organizer的IPHONE DEVELOPMENT －－－》Developer Profile里自带的Export和Import操作，不知这个方法如果实用与三个或者10个电脑其不是很BUG