If you are using a web lead provider which sends an XML post using Xpath syntax, you can select data from within the nodes for mapping incoming web leads.
For example, if the raw data being sent is formatted as:
To map these fields, you would enter:
//name[@part='first'] as the Web Form Field name for the VanillaSoft field "First Name"
//name[@part='last'] as the Web Form Field name for the VanillaSoft field "Last Name"