net.appjet.bodylock.JSRuntimeException

I meet a problem when I run /hackpad-master/bin/run.js

Here is the error info:
`Startup execution failed with error.
net.appjet.bodylock.JSRuntimeException: Error: Neither module exists: etherpad.collab.ace.easysync2, etherpad.collab.ace.easysync2.{AttribPool,Changeset}
at net.appjet.bodylock.BodyLock$.unwrapExceptionIfNecessary(bodylock.scala:160)
at net.appjet.bodylock.InnerExecutable.execute(bodylock.scala:80)
at net.appjet.oui.ScopeReuseManager$$anonfun$newRunner$1.apply$mcV$sp(servermodel.scala:127)
at net.appjet.oui.ScopeReuseManager$$anonfun$newRunner$1.apply(servermodel.scala:123)
at net.appjet.oui.ScopeReuseManager$$anonfun$newRunner$1.apply(servermodel.scala:123)
at net.appjet.oui.NoninheritedDynamicVariable.withValue(dynamicvar.scala:38)
at net.appjet.oui.ExecutionContextUtils$.withContext(execution.scala:340)
at net.appjet.oui.ScopeReuseManager$.newRunner(servermodel.scala:123)
at net.appjet.oui.ScopeReuseManager$$anonfun$getRunner$1.apply(servermodel.scala:149)
at net.appjet.oui.ScopeReuseManager$$anonfun$getRunner$1.apply(servermodel.scala:139)
at net.appjet.oui.ScopeReuseManager$.readLocked(servermodel.scala:86)
at net.appjet.oui.ScopeReuseManager$.getRunner(servermodel.scala:139)
at net.appjet.oui.execution$.runOutOfBand(execution.scala:614)
at net.appjet.oui.main$.runOnStartup(main.scala:114)
at net.appjet.oui.main$.main(main.scala:292)
at net.appjet.oui.main.main(main.scala)
Caused by: org.mozilla.javascript.JavaScriptException: foo (module preamble.js#200)
at JS$module$preamble$js$2._c_importPath_12(module preamble.js:200)
at JS$module$preamble$js$2.call(module preamble.js)
at org.mozilla.javascript.optimizer.OptRuntime.callName(OptRuntime.java:97)
at JS$module$preamble$js$2._c_anonymous_16(module preamble.js:233)
at JS$module$preamble$js$2.call(module preamble.js)
at org.mozilla.javascript.NativeArray.iterativeMethod(NativeArray.java:1563)
at org.mozilla.javascript.NativeArray.execIdCall(NativeArray.java:345)
at org.mozilla.javascript.IdFunctionObject.call(IdFunctionObject.java:129)
at org.mozilla.javascript.optimizer.OptRuntime.call1(OptRuntime.java:66)
at JS$module$preamble$js$2._c_runScheduledImports_15(module preamble.js:232)
at JS$module$preamble$js$2.call(module preamble.js)
at org.mozilla.javascript.optimizer.OptRuntime.callName0(OptRuntime.java:108)
at JS$module$preamble$js$2._c_anonymous_18(module preamble.js:272)
at JS$module$preamble$js$2.call(module preamble.js)
at org.mozilla.javascript.optimizer.OptRuntime.callProp0(OptRuntime.java:119)
at JS$module$postamble$js$253._c_script_0(module postamble.js:18)
at JS$module$postamble$js$253.call(module postamble.js)
at org.mozilla.javascript.ContextFactory.doTopCall(ContextFactory.java:426)
at org.mozilla.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3178)
at JS$module$postamble$js$253.call(module postamble.js)
at JS$module$postamble$js$253.exec(module postamble.js)
at net.appjet.bodylock.InnerExecutable$$anonfun$execute$1.apply(bodylock.scala:76)
at net.appjet.bodylock.InnerExecutable$$anonfun$execute$1.apply(bodylock.scala:75)
at net.appjet.bodylock.BodyLock$.runInContext(bodylock.scala:111)
at net.appjet.bodylock.InnerExecutable.execute(bodylock.scala:75)
... 14 more
`

I find some solution in etherpad, it tell me to Rebuild the ace dependency.
But how can I do this work in hackpad?