I am using openfire 4.0.2 with spark 2.7.7 and following is the error seen on openfire error.log.
org.jivesoftware.openfire.nio.ConnectionHandler - Closing connection due to error while processing message: <iq id="jjPRT-3672" to="roll.done@conference.xyz.com" type="set"><query xmlns="http://jabber.org/protocol/muc#owner"><x xmlns="jabber:x:data" type="submit"><field var="FORM_TYPE" type="hidden"><value>http://jabber.org/protocol/muc#roomconfig</value></field><field var="muc#roomconfig_roomname" type="text-single"><value>Roll.Done</value></field><field var="muc#roomconfig_roomdesc" type="text-single"><value>Sales&Abc</value></field><field var="muc#roomconfig_passwordprotectedroom" type="boolean"><value>1</value></field><field var="muc#roomconfig_roomsecret" type="text-private"><value>1212</value></field><field var="muc#roomconfig_roomowners" type="jid-multi"><value>roldan.ronquillo@xyz.com</value></field></x></query></iq>
org.xmlpull.v1.XmlPullParserException: entity reference name can not contain character <' (position: TEXT seen ...<value>Sales&Abc<... @1:436)
at org.xmlpull.mxp1.MXParser.parseEntityRef(MXParser.java:2222)
at org.jivesoftware.openfire.net.MXParser.nextImpl(MXParser.java:216)
at org.xmlpull.mxp1.MXParser.nextToken(MXParser.java:1100)
at org.dom4j.io.XMPPPacketReader.parseDocument(XMPPPacketReader.java:316)
at org.dom4j.io.XMPPPacketReader.read(XMPPPacketReader.java:153)
at org.jivesoftware.openfire.net.StanzaHandler.process(StanzaHandler.java:163)
at org.jivesoftware.openfire.nio.ConnectionHandler.messageReceived(ConnectionHandl er.java:181)
at org.apache.mina.core.filterchain.DefaultIoFilterChain$TailFilter.messageReceive d(DefaultIoFilterChain.java:690)
at org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(D efaultIoFilterChain.java:417)
at org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1200(DefaultIoFilt erChain.java:47)
at org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.messageReceiv ed(DefaultIoFilterChain.java:765)
at org.apache.mina.core.filterchain.IoFilterAdapter.messageReceived(IoFilterAdapte r.java:109)
at org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(D efaultIoFilterChain.java:417)
at org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1200(DefaultIoFilt erChain.java:47)
at org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.messageReceiv ed(DefaultIoFilterChain.java:765)
at org.apache.mina.filter.codec.ProtocolCodecFilter$ProtocolDecoderOutputImpl.flus h(ProtocolCodecFilter.java:407)
at org.apache.mina.filter.codec.ProtocolCodecFilter.messageReceived(ProtocolCodecF ilter.java:236)
at org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(D efaultIoFilterChain.java:417)
at org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1200(DefaultIoFilt erChain.java:47)
at org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.messageReceiv ed(DefaultIoFilterChain.java:765)
at org.apache.mina.core.filterchain.IoFilterEvent.fire(IoFilterEvent.java:74)
at org.apache.mina.core.session.IoEvent.run(IoEvent.java:63)
at org.apache.mina.filter.executor.OrderedThreadPoolExecutor$Worker.runTask(Ordere dThreadPoolExecutor.java:769)
at org.apache.mina.filter.executor.OrderedThreadPoolExecutor$Worker.runTasks(Order edThreadPoolExecutor.java:761)
at org.apache.mina.filter.executor.OrderedThreadPoolExecutor$Worker.run(OrderedThr eadPoolExecutor.java:703)
at java.lang.Thread.run(Thread.java:745)
Anyone come across this earlier?