"Oracle Web Services Inspection Language Configuration Assistant" failed ("Could not get DeploymentManager" deploying WSIL App)

Installing the 10.1.3.5 Oracle Application Server patch on an 10.1.3.1 installation, I got the following error in the "Configuration Assistants" step:

Configuration assistant "Oracle Web Services Inspection Language Configuration Assistant" failed
Buildfile: /ESB/webservices/lib/wsil-install.xml

The log windows didn't have any useful information so I took a look at the full installActions* log. This log didn't have also the concrete error but showed the complete Ant command being executed:

The command being spawned is: '/ESB/ant/bin/ant -buildfile /ESB/webservices/lib/wsil-install.xml  -logfile /ESB/cfgtoollogs/wsil.txt -DHOST=ESBDB -DOPMNPORT="6003" -DADMIN_USER=oc4jadmin -DOPMNINSTANCE=home -Denv.JAVA_HOME=/ESB/jdk -Denv.ANT_HOME=/ESB/ant -Denv.ORACLE_HOME=/ESB *Protected value, not to be logged*'

Luckily, this command had its own log file: /ESB/cfgtoollogs/wsil.txt.

This log had the following information:

[echo] Deploying WSIL App with JSSO disabled
[java] Failed at "Could not get DeploymentManager".
[java] This is typically the result of an invalid deployer URI format being supplied, the target server not being in a started state or incorrect authentication details being supplied.
[java] More information is available by enabling logging -- please see the Oracle Containers for J2EE Configuration and Administration Guide for details.

Watching other post (and other) I found this error occurs when there are errors in the arguments supplied in the deployment URL (OC4J instance, password, etc.). I looked the Ant script and found the OC4J instance being used to deploy the WSIL app was 'home', but I don't have an O4CJ instance called 'home'. My OC4J admin instance is called 'admin'.

I hardcoded the name of my real OC4J intance in the ANT buildfile, retried the action and the installation finished OK.