diff --git a/core/src/main/java/org/springframework/ws/soap/axiom/AxiomSoapMessageFactory.java b/core/src/main/java/org/springframework/ws/soap/axiom/AxiomSoapMessageFactory.java
index 3d27a8dd..6f41a2e5 100644
--- a/core/src/main/java/org/springframework/ws/soap/axiom/AxiomSoapMessageFactory.java
+++ b/core/src/main/java/org/springframework/ws/soap/axiom/AxiomSoapMessageFactory.java
@@ -199,7 +199,8 @@ public class AxiomSoapMessageFactory implements SoapMessageFactory, Initializing
         TransportInputStream transportInputStream = (TransportInputStream) inputStream;
         String contentType = getHeaderValue(transportInputStream, TransportConstants.HEADER_CONTENT_TYPE);
         if (!StringUtils.hasLength(contentType)) {
-            throw new IllegalArgumentException("TransportInputStream contains no Content-Type header");
+            logger.debug("TransportInputStream has no Content-Type header; defaulting to text/xml");
+            contentType = SoapVersion.SOAP_11.getContentType();
         }
         String soapAction = getHeaderValue(transportInputStream, TransportConstants.HEADER_SOAP_ACTION);
         if (!StringUtils.hasLength(soapAction)) {