java.lang.AbstractMethodError: bitel.billing.server.call.bean.LoginManager.checkAliases(Lbitel/billing/server/call/bean/Login;Ljava/util/Set;)Ljava/lang/String;
        at bitel.billing.server.call.ActionBase.updateLogin(ActionBase.java:263)
        at bitel.billing.server.dialup.action.ActionUpdateLoginInfo.doAction(ActionUpdateLoginInfo.java:67)
        at bitel.billing.server.Executer.doModule(Unknown Source)
        at bitel.billing.server.Executer.doPost(Unknown Source)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
        at bitel.billing.server.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:37)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:568)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
        at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
        at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
        at java.lang.Thread.run(Thread.java:619)