Genesys of a Patch

Put your patch JAR in
C:\pierre\bea103\utils\bsu\cache_dir
The JAR should have a 4 letter DNA, like I85X.jar
This jar contains a patch-descriptor.xml and a bugXXXXXXXXX.jar

Run C:\pierre\bea103\utils\bsu\bsu.cmd
Go on offline mode
Select a patch and "apply"

This will unzip the bugXXXXXXXXX.jar
to C:\pierre\bea103\patch_wls1030\patch_jars

and in C:\pierre\bea103\patch_wls1030\registry it will update a patch-registry.xml with a new patchInstallEntry

It will also update the manifest.mf in C:\pierre\bea103\patch_wls1030\profiles\default\sys_manifest_classpath\weblogic_patch.jar

(this weblogic_patch.jar contains nothing but a manifest.mf file, its only purpose is to "include" the patches in the System Classpath when we start WLS)

Probably all this will disappear with time as Oracle pushes a different Opatch tool - I don't know really. I was simply curious to understand how the patching mechanism works.