Error Getting XML from Input String

I have an affiliate who sends xml as part of a larger string like so:

User=username&Password=password&Message=[XMLDOC]&DebugMode=true

I am just grabbing the string with the request object like so and parsing the xml out of it:

Using reader As StreamReader = New StreamReader(Request.InputStream)

The problem is, they get an error on that end that states:


A potentially dangerous Request.Form value was detected from the client (Message="<?xml version="1.0" ...").

Is there a different way to go about this that I am not aware of?

And yes, I have already set the page directive to be ValidateRequest="false"
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