newrelic rpm chokes when calling exceptions/unauthenticated *without* throwing any exceptions

I've just installed newrelic_rpm 2.8.11 into my Merb application (all gems 1.0.9), and it's blowing up when I try to invoke the exceptions/unauthenticated action directly. I'm using merb-auth-slice and this exception *is* our login page.

If I try to fetch a page for which I'm not authenticated, then an unauthenticated exception is raised, and this controlller action is executed fine (and I see my login page). It's just trying to call it directly that's the problem.

Would love to get this sorted out because it's basically killing my ability to use RPM.

Here's the stack trace:

merb : worker (port 4000) ~ Started request handling: Tue May 26 08:29:26 -0400 2009
merb : worker (port 4000) ~ Params: {"format"=>nil, "action"=>"unauthenticated", "id"=>nil, "controller"=>"exceptions"}
merb : worker (port 4000) ~ undefined method `first' for nil:NilClass - (NoMethodError)
gems/gems/newrelic_rpm-2.8.11/lib/new_relic/agent/instrumentation/merb/errors.rb:3
gems/gems/merb-core-1.0.9/lib/merb-core/controller/abstract_controller.rb:348:in `instance_eval'
gems/gems/merb-core-1.0.9/lib/merb-core/controller/abstract_controller.rb:348:in `_call_filters'
gems/gems/merb-core-1.0.9/lib/merb-core/controller/abstract_controller.rb:338:in `each'
gems/gems/merb-core-1.0.9/lib/merb-core/controller/abstract_controller.rb:338:in `_call_filters'
gems/gems/merb-core-1.0.9/lib/merb-core/controller/abstract_controller.rb:283:in `_dispatch'
gems/gems/merb-core-1.0.9/lib/merb-core/controller/abstract_controller.rb:281:in `catch'
gems/gems/merb-core-1.0.9/lib/merb-core/controller/abstract_controller.rb:281:in `_dispatch'
gems/gems/merb-core-1.0.9/lib/merb-core/controller/merb_controller.rb:252:in `perform_action_without_newrelic_trace'
gems/gems/newrelic_rpm-2.8.11/lib/new_relic/agent/instrumentation/controller_instrumentation.rb:123:in `_dispatch'
gems/gems/newrelic_rpm-2.8.11/lib/new_relic/agent/method_tracer.rb:41:in `trace_method_execution_with_scope'
gems/gems/newrelic_rpm-2.8.11/lib/new_relic/agent/instrumentation/controller_instrumentation.rb:109:in `_dispatch'
gems/gems/newrelic_rpm-2.8.11/lib/new_relic/agent/method_tracer.rb:18:in `trace_method_execution_no_scope'
gems/gems/newrelic_rpm-2.8.11/lib/new_relic/agent/instrumentation/controller_instrumentation.rb:103:in `_dispatch'
gems/gems/merb-core-1.0.9/lib/merb-core/dispatch/dispatcher.rb:100:in `dispatch_action'
gems/gems/merb-core-1.0.9/lib/merb-core/dispatch/dispatcher.rb:100:in `synchronize'
gems/gems/merb-core-1.0.9/lib/merb-core/dispatch/dispatcher.rb:100:in `dispatch_action'
gems/gems/merb-core-1.0.9/lib/merb-core/dispatch/dispatcher.rb:74:in `dispatch_without_newrelic'
gems/gems/newrelic_rpm-2.8.11/lib/new_relic/agent/instrumentation/dispatcher_instrumentation.rb:44:in `handle'
gems/gems/merb-core-1.0.9/lib/merb-core/dispatch/dispatcher.rb:36:in `handle'
gems/gems/merb-core-1.0.9/lib/merb-core/rack/application.rb:17:in `call'
gems/gems/merb-core-1.0.9/lib/merb-core/rack/middleware/static.rb:28:in `call'
gems/gems/merb-core-1.0.9/lib/merb-core/rack/handler/mongrel.rb:82:in `process'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:159:in `process_client'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:158:in `each'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:158:in `process_client'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:285:in `run'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:285:in `initialize'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:285:in `new'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:285:in `run'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:268:in `initialize'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:268:in `new'
gems/gems/mongrel-1.1.5/lib/mongrel.rb:268:in `run'
gems/gems/merb-core-1.0.9/lib/merb-core/rack/adapter/mongrel.rb:38:in `start_server'
gems/gems/merb-core-1.0.9/lib/merb-core/rack/adapter/abstract.rb:295:in `start_at_port'
gems/gems/merb-core-1.0.9/lib/merb-core/rack/adapter/abstract.rb:128:in `start'
gems/gems/merb-core-1.0.9/lib/merb-core/server.rb:174:in `bootup'
gems/gems/merb-core-1.0.9/lib/merb-core/server.rb:42:in `start'
gems/gems/merb-core-1.0.9/lib/merb-core.rb:170:in `start'
gems/gems/merb-core-1.0.9/bin/merb:11
bin/merb:31:in `load'
bin/merb:31
merb : worker (port 4000) ~ Params: {"format"=>nil, "action"=>"unauthenticated", "id"=>nil, "controller"=>"exceptions"}
merb : worker (port 4000) ~