Ajax file uploading SyntaxError in ExtJs

After submitting the form with file it gives me SyntaxError <pre> </pre>in firefox , cause of this error was content type, it was application/json, to fix problem yous should change it to application/xml ( in java response.setContentType("application/xml"))

Speed up the gwt compiler

1) Add argument to the gwt compiler:
-draftCompile

2) In your *.gwt.xml specify browser, ex:
  <set-property name="user.agent" value="gecko1_8"></set-property>