Create customized zip including system.img, boot.img etc for Android customized ROM I downloaded AOSP source code and built it as instructed in its official site.
Now I have 4 img files as system, boot, recovery, userdata. I want to create a zip file which should include these files and can be installed via a recovery manager like 'Clockwork mode recovery'. 

For an example we can install CyanogenMod customized rom zip by using clockwork recovery while in boot up process of device. Like wise I need to create a zip including my own imgs.
How should the folder structure of the zipped file system should be created, what script files should be included and how that scripts should be written etc.

Used this link (http://lazydroid.com/2011/03/howto-repack-and-sign-rom-image-update-zip-files/) but how to create /META-INF/com/google/android/update-script is not well explained there.
Recently I found a source that can help you to create update-script. Here it is: http://marakana.com/s/updating_android_os_via_ota,1065/index.html