Optional(default NULL). A vector of pairs (<SOAP_method>, <PL procedure>)
mapping the SOAP call request to the corresponding PL function name.
If empty, then the mapping proceeds by taking the local name of the SOAP
method and finding a procedure with the same name in the executing
user@s current qualifier and owner.If a string is supplied then this string is considered as a PL module name.
      Mapping takes place from the local name of the SOAP call to a PL procedure inside
      the module. Virtuoso matches procedure names in case-sensitive fashion.