Rest driver in publishing mode does not handle incoming documents from application


We want to run the Rest driver as a driver that receives documents from the application in publishing mode. The application will send without requests from IDM documents.
I would expect that the driver would put these into an input document, but all we receive is a message that a document is received and than a Null Poiniter exception.

I tried to put out a resource but that basically is only on the subscriber channel, nothing to find on the publisher channel. We cannot fire a query to get these documents as a response, the application will send the messages unsolicited.

This works nicely when we use the SOAP driver, but almost same scenario on the REST driver will only do

[06/24/24 16:14:33.721]:idv - WID HUB REST :idv - WID HUB REST: Publisher channel listener received the following data:
[06/24/24 16:14:33.721]:idv - WID HUB REST :idv - WID HUB REST: {"base64Encoded":true,"message":<some message content of file2>}

And when using curl to send in the message you will receive the following, while using the classname as URI does give unavailable.

curl -i -H 'Content-Type: application/json' -k -X POST https://<IDM Server>:21443 --data-binary @file2

HTTP/1.1 100 Continue

HTTP/1.1 500 Server Error
Cache-Control: must-revalidate,no-cache,no-store
Content-Type: text/html;charset=iso-8859-1
Content-Length: 2918
Connection: close

<meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
<title>Error 500 java.lang.IllegalArgumentException</title>
<body><h2>HTTP ERROR 500 java.lang.IllegalArgumentException</h2>
<tr><th>CAUSED BY:</th><td>java.lang.IllegalArgumentException</td></tr>
<h3>Caused by:</h3><pre>java.lang.IllegalArgumentException
        at org.eclipse.jetty.server.Response.setStatus(
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(
        at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(
        at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(
        at org.eclipse.jetty.server.Server.handle(
        at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(
        at org.eclipse.jetty.server.HttpChannel.dispatch(
        at org.eclipse.jetty.server.HttpChannel.handle(
        at org.eclipse.jetty.server.HttpConnection.onFillable(
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(
        at org.eclipse.jetty.util.thread.ReservedThreadExecutor$
        at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(
        at org.eclipse.jetty.util.thread.QueuedThreadPool$