HTTP 408 gives coding error popup

[Ldp]

1. Open ​http://www.openstreetmap.org/api/0.6/relation/407255 (Mississippi river, massive multipolygon)
2. Download incomplete members

OSM server throws a 408, JOSM presents a bug popup. "This is always a coding error"

Build-Date: 2010-03-07 03:30:53
Revision: 3091
Is-Local-Build: true

Memory Usage: 31 MB / 247 MB (11 MB allocated, but free)
Java version: 1.6.0_18, Sun Microsystems Inc., Java HotSpot(TM) Client VM
Operating system: Windows XP

Dataset consistency test:
No problems found


Plugins: AddrInterpolation,multipoly,remotecontrol,terracer,validator,wmsplugin
Plugin wmsplugin Version: 19992
Plugin remotecontrol Version: 19946
Plugin validator Version: 20155
Plugin AddrInterpolation Version: 19422
Plugin terracer Version: 20084
Plugin multipoly Version: 19456

org.openstreetmap.josm.io.OsmApiException: ResponseCode=408, Error Header=<Request timed out>
	at org.openstreetmap.josm.io.OsmServerReader.getInputStreamRaw(OsmServerReader.java:110)
	at org.openstreetmap.josm.io.OsmServerReader.getInputStream(OsmServerReader.java:47)
	at org.openstreetmap.josm.io.MultiFetchServerObjectReader.multiGetIdPackage(MultiFetchServerObjectReader.java:306)
	at org.openstreetmap.josm.io.MultiFetchServerObjectReader.fetchPrimitives(MultiFetchServerObjectReader.java:420)
	at org.openstreetmap.josm.io.MultiFetchServ

[Ldp]

	at org.openstreetmap.josm.io.MultiFetchServerObjectReader.parseOsm(MultiFetchServerObjectReader.java:453)
	at org.openstreetmap.josm.gui.dialogs.relation.DownloadRelationMemberTask.realRun(DownloadRelationMemberTask.java:89)
	at org.openstreetmap.josm.gui.PleaseWaitRunnable.doRealRun(PleaseWaitRunnable.java:83)
	at org.openstreetmap.josm.gui.PleaseWaitRunnable.run(PleaseWaitRunnable.java:129)
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
	at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
	at java.util.concurrent.FutureTask.run(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)

[Gubaer]

(In [3101]) fixed #4684: HTTP 408 gives coding error popup