As per the discussion [1], the work-around was given to add 'proxyAuthScheme=http4'. But there was also a fix done for 'CAMEL-5595', what is the fix really?
Without the 'proxyAuthScheme' our HTTP calls using HTTP4 fails with - "Unrecognized SSL message, plaintext connection?" error message. Stacktrace --------------------------------------------------------------------------------------------------------------------------------------- javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection? at sun.security.ssl.InputRecord.handleUnknownRecord(InputRecord.java:671) at sun.security.ssl.InputRecord.read(InputRecord.java:504) at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:946) at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1344) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1371) at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1355) at org.apache.http.conn.ssl.SSLConnectionSocketFactory.createLayeredSocket(SSLConnectionSocketFactory.java:394) at org.apache.http.conn.ssl.SSLConnectionSocketFactory.connectSocket(SSLConnectionSocketFactory.java:353) at org.apache.http.impl.conn.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:141) at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:353) at org.apache.http.impl.execchain.MainClientExec.establishRoute(MainClientExec.java:388) Regards, Arpit. [1] - http://camel.465427.n5.nabble.com/Using-the-HTTP4-component-to-make-a-HTTPS-call-behind-proxy-sever-td5719105.html