replace word in .txt file with value in xml

Can someone help me. Here is the part of the Business.txt file

 Dim extensionParams(6) As ParameterValueOrFieldReference

    extensionParams(0) = New ParameterValue()
    CType(extensionParams(0),ParameterValue).Name = "TO"
    CType(extensionParams(0),ParameterValue).Label = ""
    CType(extensionParams(0),ParameterValue).Value = "mail@yahoo.com"

I want to replace "mail@yahoo.com" from Business.txt with the value from the xml (tag Sub Report="Business").

<Subs>
  <Sub Report="Business" EMails="lalala@yahoo.com; bla@hotmail.com">
  <Sub Report="Test" EMails="somemail@yahoo.com">
</Subs>

I need some script for that(VBScript or some other)