In the trouble shooting tips they say to keep the same encoding.
Receiving an INVALID message from PayPal in response to your listener's post back for validation "Ensure that you use the same character encoding for your response string as the encoding specified in the charset field of the original IPN message. When testing using the IPN Simulator, the character encoding will always be UTF-8."

Update: But I use PDT because "So, use PDT if your site includes a feature that requires immediate payment notification." IPN vs. PDT

Update 2: From what I can remember of IPN. It does not matter that much that it comes back "INVALID" because all that is saying is that you did not return the data back the way PayPal wanted. But the transaction still will go through and you should still receive the transaction info from the first IPN response.

Update 3: You did mention encoding and that made me think that maybe the content your getting from request->body; could be encoded or maybe decoded. Or LWP could encode the data before sending it making it a double encoded string. Just a few more things to check for.

In reply to Re^3: How do you use Paypal IPN with Dancer2? by $h4X4_|=73}{
in thread How do you use Paypal IPN with Dancer2? by MorayJ

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