Seam has a replacement for DWR named JavaScript remoting. I cover this topic in detail in chapter 12 and also draw parallel to DWR. The main difference between Seam remoting and DWR is that Seam remoting uses an XML payload, while DWR uses a JSON one. It wouldn't be impossible to bridge them, but then again, what would be the point. You simply add @WebRemote to the method of a Seam component and you can call it from JavaScript.
Java:
JavaScript: