Okay, first things first… Go read this blog post:
http://omnigeek.robmiracle.com/2012/04/15/using-corona-sdk-with-rest-api-services/
Its dealing with REST, not SOAP, but the principles are the same as far as using the network.request() API all. You probably can skip all the PHP and database bits.
Next read this blog post and get the xml.lua file from it:
http://www.coronalabs.com/blog/2011/07/29/how-to-use-xml-files-in-corona/
You will have to figure out the SOAP bits for logging in and autheticating yourself, but between the network.request() and network.download() API calls and the XML tutorial you should be able to consume SOAP data.
[import]uid: 19626 topic_id: 30212 reply_id: 121025[/import]