It may be possible to use <show-archived-real-path-enabled> on WebLogic:
http://download.oracle.com/docs/cd/E11035_01/wls100/issues/known_resolved.html
If you deploy a web app as an archive war file, then context.getRealPath() returns null. This behavior can lead to certain failures in cases where the web app is dependent on the path.
Solution:
Use the <show-archived-real-path-enabled> flag to specify that context.getRealPath() returns the path of the resource from the Server's internal webapp extraction directory for archived web applications. The flag can be configured in two ways:
At domain level in config.xml. For example:
<web-app-container>
<show-archived-real-path-enabled>true
</show-archived-real-path-enabled>
</web-app-container>
At the web app level in weblogic.xml. For example:
<container-descriptor>
<show-archived-real-path-enabled>true
</show-archived-real-path-enabled>
</container-descriptor>
The value of <show-archived-real-path-enabled> set in the web app has precedence over the value set at the domain level. The default value of this property is false.
Note that, if this path is used to dynamically copy some content to this directory location, the content will end up in the Server's internal web app extraction directory. When the web app is recompiled for any reason, the web app may be re-extracted and previously copied content will be lost.
Attached war file that is ready to be deployed on WebLogic.