This is AIX :)
We're having this problem as well. I ran the command that ant is running directly from the command line and the following happened:
bash-3.00$ bin/asadmin create-domain --adminport 4848 --instanceport 8080 --user admin --passwordfile passfile --domainproperties orb.listener.port=3700:jms.port=7676:http.ssl.port=8181 --savelogin domain1
Using port 4848 for Admin.
Using port 8080 for HTTP Instance.
Using port 7676 for JMS.
Using port 3700 for IIOP.
Using port 8181 for HTTP_SSL.
Using default port 3820 for IIOP_SSL.
Using default port 3920 for IIOP_MUTUALAUTH.
Using default port 8686 for JMX_ADMIN.
Domain being created with profile:developer, as specified by variable AS_ADMIN_PROFILE in configuration file.
Security Store uses: JKS
File {0} not found.
CLI130 Could not create domain, domain1
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