Was able to resolve this issue... The problem was our route started with an IMAP consumer which passed on the header all the way to the SMTP endpoint which resulted in the exception. We were able to work around this by adding this to the route:
<removeHeaders pattern="*" /> Thanks, Nap -- View this message in context: http://camel.465427.n5.nabble.com/SMTP-Endpoint-tp4450247p4483515.html Sent from the Camel - Users mailing list archive at Nabble.com.