I believe the best way to that would be to write a web service that SSIS would use to push the data into SQL. However, this is not a trivial thing to accomplish. There are a lot of things to consider when building a custom applicaiton like this including the fact that you will need to write a web service for every InfoPath template you want mapped to SQL (since the InfoPath schema is different for each form template).
You should take a look at our DBXL tool - http://www.qdabra.com/en/products/DBXL.aspx.
DBXL is a generic web service that easily integrates with InfoPath and or SharePoint (although SharePoint is not required). DBXL includes tools to help you map your data to SQL and can be used any number of InfoPath forms and all without code.
If you are interested in talking more about our product feel free send me a private message. I can even demo the tool to you and show you how easy it is to use.
Ted