ListFiles component throws NPE for root directory of ftp

<?xml version="1.0" encoding="UTF-8"?>
<Graph author="XXX" created="Wed Mar 22 16:30:51 CET 2017" guiVersion="4.6.0.M1" id="1490196693475" licenseCode="XXX" name="g" showComponentDetails="true">
<Global>
<GraphParameters>
<GraphParameterFile fileURL="workspace.prm"/>
</GraphParameters>
<Dictionary/>
</Global>
<Phase number="0">
<Node fileURL="ftp://supportint:*****@ftpserver/" guiName="ListFiles" guiX="196" guiY="215" id="LIST_FILES" listDirectoryContents="false" type="LIST_FILES"/>
<Node guiName="Trash" guiX="616" guiY="204" id="TRASH" type="TRASH"/>
<Edge fromNode="LIST_FILES:0" guiBendpoints="" guiRouter="Manhattan" id="Edge0" inPort="Port 0 (in)" outPort="Port 0 (out)" toNode="TRASH:0"/>
</Phase>
</Graph>

16:01:48,363 ERROR [WatchDog_19] Error details:
org.jetel.exception.JetelRuntimeException: Component [ListFiles:LIST_FILES] finished with status ERROR. (Out0: 0 recs)
	at org.jetel.graph.Node.createNodeException(Node.java:636)
	at org.jetel.graph.Node.run(Node.java:603)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
	at org.jetel.component.fileoperation.PooledFTPOperationHandler$FTPInfo.getLastModified(PooledFTPOperationHandler.java:180)
	at com.opensys.cloveretl.component.ListFiles.populateResultRecord(Main:198)
	at com.opensys.cloveretl.component.AbstractFileOperation.processStandardOutputMapping(Main:591)
	at com.opensys.cloveretl.component.AbstractFileOperation.processSuccess(Main:521)
	at com.opensys.cloveretl.component.ListFiles.processResult(Main:239)
	at com.opensys.cloveretl.component.AbstractFileOperation.mainExecuteOperation(Main:351)
	at com.opensys.cloveretl.component.AbstractFileOperation.execute(Main:388)
	at org.jetel.graph.Node.run(Node.java:563)
	... 3 more