The customer is doing JMS-based webservices using the following declarations in their wsdl file (referred to using the wsdllocation annotation):
<soapjms:jndiConnectionFactoryName>myqueue</soapjms:jndiConnectionFactoryName> <soapjms:jndiInitialContextFactory>com.vendor.InitialContextFactory</soapjms:jndiInitialContextFactory>
<soapjms:jndiURL>$MY_URL</soapjms:jndiURL>

The $MY_URL is the url of the messaging server. Since property replacement does not work for wsdl files they need to manually modify this before deploying and package separate versions of their app for each environment. If property expansion worked in the .wsdl this would no longer be necessary.