The version of the campfire notifier plugin you get using the jenkins UI package manager is 2.1, but the latest on the github project page is 2.5: https://github.com/jenkinsci/campfire-plugin
There have been lots of nice improvements and bug fixes since 2.1, notably Brad Greenlee's SmartNotify fix https://github.com/jenkinsci/campfire-plugin/commit/999248d14d0f19697d92ce35ed431f69b97b894d (hi, Brad!) I just built the plugin from source and installed it, but is there any reason the plugin on the UI is so old? Can that be updated?