Dieter 0.4.0 is failing to work

[piranha]

I've updated Dieter to 0.4.0 from 0.3.0 and now it fails with following stacktrace:

Exception: java.lang.IllegalArgumentException: No implementation of method: :make-reader of protocol: #'clojure.java.io/IOFactory found for class: nil
                         core_deftype.clj:541 clojure.core/-cache-protocol-fn
                                    io.clj:73 clojure.java.io/fn[fn]
                                   io.clj:106 clojure.java.io/reader
                              RestFn.java:410 clojure.lang.RestFn.invoke
                                 rhino.clj:63 dieter.rhino/load-vendor
                                 rhino.clj:15 dieter.rhino/new-scope
                              jsengine.clj:16 dieter.jsengine/run-compiler[fn]
                                 pools.clj:20 dieter.pools/get-from-pool
                              jsengine.clj:16 dieter.jsengine/run-compiler
                              RestFn.java:470 clojure.lang.RestFn.invoke
                                  less.clj:13 dieter.asset.less/preprocess-less
                                  less.clj:22 dieter.asset.less/dieter.asset.less.Less
                                  core.clj:68 dieter.core/find-and-cache-asset
                                  core.clj:78 dieter.core/asset-builder[fn]
                             file_info.clj:40 ring.middleware.file-info/wrap-file-info[fn]
                                  core.clj:55 dieter.core/wrap-dieter-mime-types[fn]
                             file_info.clj:40 ring.middleware.file-info/wrap-file-info[fn]
                                 Var.java:415 clojure.lang.Var.invoke
                                reload.clj:18 ring.middleware.reload/wrap-reload[fn]
                            stacktrace.clj:15 ring.middleware.stacktrace/wrap-stacktrace-log[fn]
                            stacktrace.clj:79 ring.middleware.stacktrace/wrap-stacktrace-web[fn]
                                 jetty.clj:18 ring.adapter.jetty/proxy-handler[fn]
                             (Unknown Source) ring.adapter.jetty.proxy$org.eclipse.jetty.server.handler.AbstractHandler$0.handle
                      HandlerWrapper.java:116 org.eclipse.jetty.server.handler.HandlerWrapper.handle
                              Server.java:363 org.eclipse.jetty.server.Server.handle
              AbstractHttpConnection.java:483 org.eclipse.jetty.server.AbstractHttpConnection.handleRequest
              AbstractHttpConnection.java:920 org.eclipse.jetty.server.AbstractHttpConnection.headerComplete
              AbstractHttpConnection.java:982 org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete
                          HttpParser.java:635 org.eclipse.jetty.http.HttpParser.parseNext
                          HttpParser.java:235 org.eclipse.jetty.http.HttpParser.parseAvailable
                  AsyncHttpConnection.java:82 org.eclipse.jetty.server.AsyncHttpConnection.handle
               SelectChannelEndPoint.java:628 org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle
                SelectChannelEndPoint.java:52 org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run
                    QueuedThreadPool.java:608 org.eclipse.jetty.util.thread.QueuedThreadPool.runJob
                    QueuedThreadPool.java:543 org.eclipse.jetty.util.thread.QueuedThreadPool$3.run
                              Thread.java:722 java.lang.Thread.run