Web Service is as follows:

---------------
LSEndpoint.java
---------------

package com.plesk.ka.ejb.webservice;

import com.plesk.ka.model.account.AccountInfo;

public interface LSEndpoint extends java.rmi.Remote
{
AccountInfo getAccountInfo( int accountId ) throws java.rmi.RemoteException;
}

-----------
LSBean.java
-----------

package com.plesk.ka.ejb.webservice;

import com.plesk.ka.util.log.Log;
import com.plesk.ka.ejb.account.AccountManagerRemoteHome;
import com.plesk.ka.ejb.account.AccountManagerRemote;
import com.plesk.ka.model.account.AccountInfo;

import javax.naming.NamingException;
import javax.naming.Context;

import javax.ejb.EJBException;
import javax.rmi.PortableRemoteObject;

import java.rmi.RemoteException;

public class LSBean implements javax.ejb.SessionBean, LSEndpoint
{
public Context jndiContext;

public AccountInfo getAccountInfo( int accountId )
{
Log.debug( "LSBean.getAccountInfo" );

try

{ Object ref = jndiContext.lookup( "AccountManager" ); AccountManagerRemoteHome home = (AccountManagerRemoteHome) PortableRemoteObject.narrow( ref, AccountManagerRemoteHome.class ); AccountManagerRemote remote = home.create(); AccountInfo accountInfo = remote.getAccount( accountId ); return accountInfo; }

catch( Exception e )

{ e.printStackTrace(); throw new EJBException( e ); }

}

public void ejbCreate()
{
}

public void ejbRemove()
{
}

public void ejbActivate()
{
}

public void ejbPassivate()
{
}

public void setSessionContext( javax.ejb.SessionContext cntx )
{
try

{ jndiContext = new javax.naming.InitialContext(); }

catch( NamingException ne )

{ throw new EJBException( ne ); }

}

}

----------------
AccountInfo.java
----------------

package com.plesk.ka.model.account;

import com.plesk.ka.util.validation.Validator;

import java.util.Date;

public class AccountInfo implements java.io.Serializable, Cloneable
{

public final static long NO_ID = -1;
public final static long ROOT_ID = 0;

public final static String ADMIN = "Admin";
public final static String RESELLER = "Reseller";
public final static String CLIENT = "Client";

private String id = "";
private String resellerId = "";
private String resellerName = "";
private String role = "";
private Boolean blocked = null;
private Date creationDate = null;
private Date modificationDate = null;
private String name = "";
private String company = "";
private String email = "";

public AccountInfo()
{
}

public String getId()

{ return id; }

public void setId( String id )

{ this.id = id; }

public String getResellerId()

{ return resellerId; }

public void setResellerId( String resellerId )

{ this.resellerId = resellerId; }

public String getResellerName()

{ return resellerName; }

public void setResellerName( String resellerName )

{ this.resellerName = resellerName; }

public String getRole()

{ return role; }

public void setRole( String role )

{ this.role = role; }

public boolean isBlocked()

{ return blocked.booleanValue(); }

public Boolean getBlocked()

{ return blocked; }

public void setBlocked( boolean blocked )

{ this.blocked = new Boolean( blocked ); }

public Date getCreationDate()

{ return creationDate; }

public void setCreationDate( Date creationDate )

{ this.creationDate = creationDate; }

public Date getModificationDate()

{ return modificationDate; }

public void setModificationDate( Date modificationDate )

{ this.modificationDate = modificationDate; }

public String getName()

{ return name; }

public void setName( String name )

{ this.name = name; }

public String getCompany()

{ return company; }

public void setCompany( String company )

{ this.company = company; }

public String getEmail()

{ return email; }

public void setEmail( String email )

{ this.email = email; }

public boolean isFiltered()

{ return id.length() != 0 || resellerId.length() != 0 || resellerName.length() != 0 || role.length() != 0 || blocked != null || creationDate != null || modificationDate != null || name.length() != 0 || company.length() != 0 || email.length() != 0; }

public boolean isValidData()

{ if( Validator.checkNameNumber( name ) != null ) return false; if( Validator.checkNameNumber( company ) != null ) return false; if( Validator.checkEmail( email ) != null ) return false; return true; }

public Object clone()
{
try

{ return super.clone(); }

catch( CloneNotSupportedException e )

{ return null; }

}

}

------------
ejb-jar.xml:
------------

<?xml version="1.0"?>

<!-- @version $Id:$ -->

<ejb-jar
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/ejb-jar_2_1.xsd"
version="2.1">

<enterprise-beans>

<!-- LS -->
<session>
<description>LS Web Service</description>
<ejb-name>LSEjbEndpoint</ejb-name>
<service-endpoint>com.plesk.ka.ejb.webservice.LSEndpoint</service-endpoint>
<ejb-class>com.plesk.ka.ejb.webservice.LSBean</ejb-class>
<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>
<security-identity><use-caller-identity/></security-identity>
</session>

</enterprise-beans>

<!-- Security area -->

<assembly-descriptor>

<security-role>
<role-name>System</role-name>
</security-role>

<security-role>
<role-name>Admin</role-name>
</security-role>

<method-permission>
<role-name>System</role-name>
<role-name>Admin</role-name>
<role-name>Accounts Manager</role-name>
<method>
<ejb-name>LSEjbEndpoint</ejb-name>
<method-name>*</method-name>
</method>
</method-permission>

</assembly-descriptor>

</ejb-jar>

----------
jboss.xml:
----------

<?xml version="1.0"?>

<!-- @version $Id:$ -->

<!DOCTYPE jboss PUBLIC "-//JBoss//DTD JBOSS 4.0//EN" "http://www.jboss.org/j2ee/dtd/jboss_4_0.dtd">

<jboss>

<security-domain>java:/jaas/ka-ls</security-domain>

</jboss>

---------------
webservices.xml
---------------

<?xml version='1.0' encoding='UTF-8' ?>

<webservices
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:ka="http://ka.plesk.com/LS"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://www.ibm.com/webservices/xsd/j2ee_web_services_1_1.xsd"
version="1.1">

<webservice-description>
<webservice-description-name>LSService</webservice-description-name>
<wsdl-file>META-INF/wsdl/ls.wsdl</wsdl-file>
<jaxrpc-mapping-file>META-INF/ls_mapping.xml</jaxrpc-mapping-file>
<port-component>
<port-component-name>LSEndpoint</port-component-name>
<wsdl-port>ka:LSEndpoint</wsdl-port>
<service-endpoint-interface>com.plesk.ka.ejb.webservice.LSEndpoint</service-endpoint-interface>
<service-impl-bean>
<ejb-link>LSEjbEndpoint</ejb-link>
</service-impl-bean>
</port-component>
</webservice-description>

</webservices>

--------------
ls_mapping.xml
--------------

<?xml version='1.0' encoding='UTF-8' ?>

<java-wsdl-mapping
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://www.ibm.com/webservices/xsd/j2ee_jaxrpc_mapping_1_1.xsd"
version="1.1">

<package-mapping>
<package-type>com.plesk.ka.ejb.webservice</package-type>
<namespaceURI>http://webservice.ejb.ka.plesk.com/LSEndpoint</namespaceURI>
</package-mapping>

<package-mapping>
<package-type>com.plesk.ka.model.account</package-type>
<namespaceURI>http://account.model.ka.plesk.com</namespaceURI>
</package-mapping>

</java-wsdl-mapping>

-------
ls.wsdl
-------

<?xml version="1.0" encoding="UTF-8"?>
<wsdl:definitions targetNamespace="http://webservice.ejb.ka.plesk.com" xmlns:impl="http://webservice.ejb.ka.plesk.com" xmlns:intf="http://webservice.ejb.ka.plesk.com" xmlns:apachesoap="http://xml.apache.org/xml-soap" xmlns:wsdlsoap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:tns2="http://account.model.ka.plesk.com" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns="http://schemas.xmlsoap.org/wsdl/">
<wsdl:types>
<schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="http://account.model.ka.plesk.com">
<import namespace="http://schemas.xmlsoap.org/soap/encoding/"/>
<complexType name="AccountInfo">
<sequence>
<element name="blocked" type="xsd:boolean"/>
<element name="company" nillable="true" type="xsd:string"/>
<element name="creationDate" nillable="true" type="xsd:dateTime"/>
<element name="email" nillable="true" type="xsd:string"/>
<element name="filtered" type="xsd:boolean"/>
<element name="id" nillable="true" type="xsd:string"/>
<element name="modificationDate" nillable="true" type="xsd:dateTime"/>
<element name="name" nillable="true" type="xsd:string"/>
<element name="resellerId" nillable="true" type="xsd:string"/>
<element name="resellerName" nillable="true" type="xsd:string"/>
<element name="role" nillable="true" type="xsd:string"/>
<element name="validData" type="xsd:boolean"/>
</sequence>
</complexType>
</schema>
</wsdl:types>

<wsdl:message name="getAccountInfoResponse">

<wsdl:part name="getAccountInfoResponse" type="tns2:AccountInfo"/>

</wsdl:message>

<wsdl:message name="getAccountInfoRequest">

<wsdl:part name="in0" type="xsd:int"/>

</wsdl:message>

<wsdl:portType name="LSEndpoint">

<wsdl:operation name="getAccountInfo" parameterOrder="in0">

<wsdl:input name="getAccountInfoRequest" message="impl:getAccountInfoRequest"/>

<wsdl:output name="getAccountInfoResponse" message="impl:getAccountInfoResponse"/>

</wsdl:operation>

</wsdl:portType>

<wsdl:binding name="LSEndpointSoapBinding" type="impl:LSEndpoint">

<wsdlsoap:binding style="rpc" transport="http://schemas.xmlsoap.org/soap/http"/>

<wsdl:operation name="getAccountInfo">

<wsdlsoap:operation soapAction=""/>

<wsdl:input name="getAccountInfoRequest">

<wsdlsoap:body use="literal" namespace="http://webservice.ejb.ka.plesk.com"/>

</wsdl:input>

<wsdl:output name="getAccountInfoResponse">

<wsdlsoap:body use="literal" namespace="http://webservice.ejb.ka.plesk.com"/>

</wsdl:output>

</wsdl:operation>

</wsdl:binding>

<wsdl:service name="LSEndpointService">

<wsdl:port name="LSEndpoint" binding="impl:LSEndpointSoapBinding">

<wsdlsoap:address location="http://localhost:2000/ka-ls/LSService"/>

</wsdl:port>

</wsdl:service>

</wsdl:definitions>

-------------------------------------
A web service is called on client as:

CallbackHandler handler = new UsernamePasswordHandler( "admin", "password".toCharArray() );
LoginContext lc = new LoginContext( "other", handler );
lc.login();

ServiceFactory serviceFactory = ServiceFactory.newInstance();
Service service = serviceFactory.createService(
new URL( "http://localhost:2000/ka-ls/LSService?WSDL" ),
new QName( "http://webservice.ejb.ka.plesk.com", "LSEndpointService" ) );
LSEndpoint endpoint = (LSEndpoint) service.getPort( LSEndpoint.class );
AccountInfo accountInfo = endpoint.getAccountInfo( 0 );
System.out.println( "AccountInfo: " + accountInfo.getName() );

lc.logout();

--------------------------------------------

So it works fine on jboss-4.0.2RC1+j2sdk1.4.2_05, but on jdk1.5.0_02 it throws:
(while calling endpoint.getAccountInfo( 0 ))

run.test:
[java] KA console test started...
[java] log4j:WARN No appenders could be found for logger (org.jboss.webservice.EngineConfigurationFinder).
[java] log4j:WARN Please initialize the log4j system properly.
[java] java.rmi.RemoteException: null; nested exception is:
[java] java.lang.NullPointerException
[java] at org.jboss.webservice.client.PortProxy.invoke(PortProxy.java:176)
[java] at $Proxy1.getAccountInfo(Unknown Source)
[java] at com.plesk.ka.util.test.ConsoleTest.testWS(ConsoleTest.java:231)
[java] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[java] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
[java] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
[java] at java.lang.reflect.Method.invoke(Method.java:585)
[java] at com.plesk.ka.util.test.ConsoleTest.main(ConsoleTest.java:77)
[java] Caused by: java.lang.NullPointerException
[java] at java.util.Hashtable.put(Hashtable.java:396)
[java] at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl.setProperty(SAXParserImpl.java:395)
[java] at org.jboss.axis.encoding.DeserializationContextImpl.parse(DeserializationContextImpl.java:262)
[java] at org.jboss.axis.MessagePart.getAsSOAPEnvelope(MessagePart.java:684)
[java] at org.jboss.axis.Message.getSOAPEnvelope(Message.java:428)
[java] at org.jboss.axis.Message.getContentType(Message.java:494)
[java] at org.jboss.axis.transport.http.HTTPSender.writeToSocket(HTTPSender.java:386)
[java] at org.jboss.axis.transport.http.HTTPSender.invoke(HTTPSender.java:126)
[java] at org.jboss.axis.strategies.InvocationStrategy.visit(InvocationStrategy.java:73)
[java] at org.jboss.axis.SimpleChain.doVisiting(SimpleChain.java:160)
[java] at org.jboss.axis.SimpleChain.invoke(SimpleChain.java:123)
[java] at org.jboss.webservice.client.ClientEngine.invoke(ClientEngine.java:128)
[java] at org.jboss.axis.client.Call.invokeEngine(Call.java:3054)
[java] at org.jboss.axis.client.Call.invoke(Call.java:3039)
[java] at org.jboss.axis.client.Call.invoke(Call.java:2629)
[java] at org.jboss.axis.client.Call.invoke(Call.java:2538)
[java] at org.jboss.axis.client.Call.invokeInternal(Call.java:1976)
[java] at org.jboss.axis.client.Call.invoke(Call.java:1914)
[java] at org.jboss.webservice.client.CallImpl.invoke(CallImpl.java:265)
[java] at org.jboss.axis.client.AxisClientProxy.invoke(AxisClientProxy.java:381)
[java] at $Proxy0.getAccountInfo(Unknown Source)
[java] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[java] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
[java] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
[java] at java.lang.reflect.Method.invoke(Method.java:585)
[java] at org.jboss.webservice.client.PortProxy.invoke(PortProxy.java:105)
[java] ... 7 more

Also, when trying to call WebService from another Bean not thru the ServiceFactory it works fine on both jdk 1.4 and 1.5 (may be it'll help somehow):

javax.naming.Context jndiContext = new InitialContext();
Object obj = jndiContext.lookup( "java:comp/env/service/LS" );
javax.xml.rpc.Service svc = (javax.xml.rpc.Service) obj;
LSEndpoint endpoint = (LSEndpoint) svc.getPort( LSEndpoint.class );
return endpoint.getAccountInfo( accountId );

run.test:
[java] KA console test started...
[java] log4j:WARN No appenders could be found for logger (org.jboss.webservice.EngineConfigurationFinder).
[java] log4j:WARN Please initialize the log4j system properly.
[java] AccountInfo: SWsoft