To apply patches on top of AIA 10g you need a Standalone patch.
In my case, i had to apply a patch on top of AIA 2.5 version.
-I had to apply a Stand alone patch. The version used is stand alone opatch 18.104.22.168.0 . this can be downloaded from the oracle support site.
-After applying the stand alone patch, you can apply the aia update patch. .
- opatch apply -oh <AIA_HOME> -jre <SOA_HOME>/jre/1.4.2
AIA_HOME - Complete directory path where AIA_HOME is installed
SOA_HOME - Complete directory path where SOA is installed
Follow the instructions given in the readme and should be able to do it.