title: RestEasy 2.3.5 Client Issue
body: <p>I am very new to Rest Easy.</p>
  
  <p>I have recently added RestEasy to my Grails project. It already had some crawler library working. I am getting the below exception and I am not sure what jars etc are conflicting or what is the root cause. I am using JDK 1.7</p>
  
  <p>Since I am getting this on below line of code (while getting the instance) I am thinking that this is a jar conflict issue</p>
  
  <pre><code>ResteasyProviderFactory.getInstance()
  
  
  
  | Error Caused by: java.lang.RuntimeException: Unable to instantiate MessageBodyWriter
  | Error     at   org.jboss.resteasy.spi.ResteasyProviderFactory.registerProvider(ResteasyProviderFactory.java:849)
  | Error     at org.jboss.resteasy.plugins.providers.RegisterBuiltin.registerProviders(RegisterBuiltin.java:70)
  | Error     at org.jboss.resteasy.plugins.providers.RegisterBuiltin.register(RegisterBuiltin.java:31)
  | Error     ... 13 more
  | Error Caused by: java.lang.ClassCastException: com.sun.proxy.$Proxy28 cannot be cast to javax.ws.rs.Produces
  | Error     at org.jboss.resteasy.spi.ResteasyProviderFactory.addMessageBodyWriter(ResteasyProviderFactory.java:566)
  | Error     at org.jboss.resteasy.spi.ResteasyProviderFactory.addMessageBodyWriter(ResteasyProviderFactory.java:536)
  | Error     at org.jboss.resteasy.spi.ResteasyProviderFactory.registerProvider(ResteasyProviderFactory.java:845)
  | Error     ... 15 more
  </code></pre>
  
  <p>Apart from grails configured plugin and jars I have the below jars in my path</p>
  
  <pre><code>activation.jar
  apache-mime4j-benchmark-0.7.2.jar
  apache-mime4j-core-0.7.2.jar
  apache-mime4j-dom-0.7.2.jar
  apache-mime4j-examples-0.7.2.jar
  apache-mime4j-storage-0.7.2.jar
  asm-3.1.jar
  attributes.jar
  boilerpipe-1.1.0.jar
  commons-beanutils-1.8.3.jar
  commons-codec-1.6.jar
  commons-compress-1.3.jar
  commons-io-2.1.jar
  commons-logging-1.1.1.jar
  commons-net-3.2.jar
  crawler4j-3.5.jar
  ebaycalls.jar
  ebaysdkcore.jar
  FastInfoset.jar
  geronimo-stax-api_1.0_spec-1.0.1.jar
  helper.jar
  http.jar
  httpclient-4.2.3.jar
  httpcore-4.2.2.jar
  httpmime-4.2.3.jar
  jackson-core-asl-1.9.9.jar
  jackson-jaxrs-1.9.9.jar
  jackson-mapper-asl-1.9.9.jar
  jackson-xc-1.9.9.jar
  jakarta-oro-2.0.8.jar
  jaxb-api.jar
  jaxb-impl.jar
  jaxb-xjc.jar
  jaxrs-api-2.3.5.Final.jar
  jaxws-api.jar
  jaxws-rt.jar
  jaxws-tools.jar
  je-4.0.92.jar
  jsoup-1.7.1.jar
  jsr173_api.jar
  jsr181-api.jar
  jsr250-api.jar
  list
  log4j-1.2.16.jar
  metadata-extractor-2.4.0-beta-1.jar
  mimepull.jar
  opencsv-2.3.jar
  resolver.jar
  resteasy-atom-provider-2.3.5.Final.jar
  resteasy-cache-core-2.3.5.Final.jar
  resteasy-cdi-2.3.5.Final.jar
  resteasy-crypto-2.3.5.Final.jar
  resteasy-fastinfoset-provider-2.3.5.Final.jar
  resteasy-guice-2.3.5.Final.jar
  resteasy-jackson-provider-2.3.5.Final.jar
  resteasy-jaxb-provider-2.3.5.Final.jar
  resteasy-jaxrs-2.3.5.Final.jar
  resteasy-jettison-provider-2.3.5.Final.jar
  resteasy-jsapi-2.3.5.Final.jar
  resteasy-links-2.3.5.Final.jar
  resteasy-multipart-provider-2.3.5.Final.jar
  resteasy-oauth-2.3.5.Final.jar
  resteasy-spring-2.3.5.Final.jar
  resteasy-yaml-provider-2.3.5.Final.jar
  saaj-api.jar
  saaj-impl.jar
  serializer.jar
  sjsxp.jar
  solr-core-4.2.0.jar
  solr-solrj-4.2.0.jar
  stax-ex.jar
  streambuffer.jar
  tagsoup-1.2.1.jar
  tika-app-1.2.jar
  tika-bundle-1.2.jar
  xalan.jar
  </code></pre>