Damn it!
I spent several days hunting down this "bug".
My Camel fragment worked at home (ubuntu) but not at work (windows).
The same fragment, the same settings in eclipse but at home I got nice
xml output from marshal().xstream() and at work I got just empty body in
my traces. Finally I discovered that home "output console encoding" was
utf-8 when at work CP-1252. So camel worked properly, I just could not
see the output because of console encoding setting in Eclipse!
Just felt like sharing :)
Vadim.