Uncaught exception with weborb and flex sdk>4.6

Hi,
there was a quite similar discussion a while ago and I wanted to ask if
someone found a solution.
I want to use weborbForJava for remoting purposes. when I use flex 4.9 and
later I always get a compiler error (in Flash Builder an uncaught exception
and in intelliJ an unknown error). It shows up when I add the
service-config.xml to the compiler arguments.
Same Project compiles just fine with flex 4.6.
Can anyone help me out with that?
thank you

the log if it helps:
java.lang.NullPointerException
at flex2.compiler.CompilerAPI.getMessagingClasses(CompilerAPI.java:1730)
at flex2.compiler.CompilerAPI.compile(CompilerAPI.java:1538)
at flex2.tools.oem.Application.compile(Application.java:1357)
at flex2.tools.oem.Application.recompile(Application.java:1295)
at flex2.tools.oem.Application.compile(Application.java:894)
at
flex2.tools.flexbuilder.BuilderApplication.compile(BuilderApplication.java:367)
at
com.adobe.flexbuilder.multisdk.compiler.internal.ASApplicationBuilder$MyBuilder.mybuild(ASApplicationBuilder.java:309)
at
com.adobe.flexbuilder.multisdk.compiler.internal.ASApplicationBuilder.build(ASApplicationBuilder.java:128)
at
com.adobe.flexbuilder.multisdk.compiler.internal.ASBuilder.build(ASBuilder.java:203)
at
com.adobe.flexbuilder.multisdk.compiler.internal.ASItemBuilder.build(ASItemBuilder.java:93)
at
com.adobe.flexbuilder.project.compiler.internal.FlexProjectBuilder.buildItem(FlexProjectBuilder.java:708)
at
com.adobe.flexbuilder.project.compiler.internal.FlexProjectBuilder.build(FlexProjectBuilder.java:412)
at
com.adobe.flexbuilder.project.compiler.internal.FlexIncrementalBuilder.build(FlexIncrementalBuilder.java:171)
at
org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:728)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at
org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:199)
at
org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:239)
at
org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:292)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at
org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:295)
at
org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:351)
at
org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:374)
at
org.eclipse.core.internal.resources.Workspace.buildInternal(Workspace.java:513)
at org.eclipse.core.internal.resources.Workspace.build(Workspace.java:422)
at
org.eclipse.ui.actions.GlobalBuildAction$1.run(GlobalBuildAction.java:180)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)