UTL_HTTP with ws-security without plain text authentication

Profile is Oracle Database12.1 EBS, and Oracle SOA Suite 12.1.  The bpel services in SOA suite are protected using ws-security and we would like to call the services from the database without exposing the username and password as plain text.  We are using UTL_HTTP and passing the ws-security with hard coded username/password.  We have multiple instances of dev and test and have contemplated encrypting these as profile options but are looking for an alternative.

It appears the Oracle wallet does not support ws-security but only basic and aws.  Is there a way to use 'basic' in the wallet then retrieve and plug the username and password into the xml ws-security header?