title: Incompatible Class Change Error: jaxrs-0.7 vs mail-1.0.1
body: <p>I have a dependency resolution issue with another plugin, which is causing the following error:</p>
  
  <pre><code>Caused by: java.lang.IncompatibleClassChangeError
  at grails.plugin.mail.MailMessageContentRenderer$RenderEnvironment.init(MailMessageContentRenderer.groovy:125)
  at grails.plugin.mail.MailMessageContentRenderer$RenderEnvironment.with(MailMessageContentRenderer.groovy:158)
  at grails.plugin.mail.MailMessageContentRenderer.render(MailMessageContentRenderer.groovy:47)
  at grails.plugin.mail.MailMessageBuilder.doRender(MailMessageBuilder.groovy:235)
  at grails.plugin.mail.MailMessageBuilder.html(MailMessageBuilder.groovy:253)
  </code></pre>
  
  <p>The way to recreate the error:
  Install jaxrs 0.7 plugin and its dependencies in build config: spock 0.7 and org.springframework:spring-test:3.1.2.RELEASE</p>
  
  <p>When I do run-app, since everything is loaded directly from resources, there is no error. However, doing a run-war, as dependencies are resolved I get the the above error.</p>
  
  <p>The mail plugin depends on org.springframework:spring-test:3.1.0.RELEASE which gets kicked out. So, probably that is the reason.</p>
  
  <p>Any suggestions on how to deal with this issue? I don't necessarily want to recompile the plugin separately as it becomes hard to maintain. I already tried a lot of combination in buildconfig for exclusion, but doesn't seem to work.</p>
  
  <p>Thanks.</p>