Getting Internal Server Error when changing kickstart profile's operating system on Red Hat Satellite 5.6

Issue

• "Internal Server Error" (ISE) while changing operating system version for Kickstart profiles,followed by this traceback:

Exception:
javax.servlet.ServletException
    at org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:535)
    at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:433)
    at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:237)
    at com.redhat.rhn.frontend.struts.RhnRequestProcessor.process(RhnRequestProcessor.java:99)
    at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
    at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at com.redhat.rhn.frontend.servlets.AuthFilter.doFilter(AuthFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:142)
    at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:58)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at com.redhat.rhn.frontend.servlets.LocalizedEnvironmentFilter.doFilter(LocalizedEnvironmentFilter.java:67)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at com.redhat.rhn.frontend.servlets.EnvironmentFilter.doFilter(EnvironmentFilter.java:108)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at com.redhat.rhn.frontend.servlets.SessionFilter.doFilter(SessionFilter.java:55)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at com.redhat.rhn.frontend.servlets.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:97)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:210)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
    at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:200)
    at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:291)
    at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:775)
    at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:704)
    at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:897)
    at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:685)
    at java.lang.Thread.run(Thread.java:736)
Caused by: java.lang.NullPointerException
    at com.redhat.rhn.manager.kickstart.cobbler.CobblerProfileCommand.updateCobblerFields(CobblerProfileCommand.java:96)
    at com.redhat.rhn.manager.kickstart.cobbler.CobblerProfileEditCommand.store(CobblerProfileEditCommand.java:59)
    at com.redhat.rhn.frontend.action.kickstart.KickstartSoftwareEditAction.processFormValues(KickstartSoftwareEditAction.java:235)
    at com.redhat.rhn.frontend.action.kickstart.BaseKickstartEditAction.execute(BaseKickstartEditAction.java:80)
    at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
    ... 40 more