RS in table sort

https://xyz.olat.com/auth/CoachSite/0/Members/0/Identity/251297813/RepositoryEntry/149291008
Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/48.0.2564.103 Safari/537.36
**RedScreen** exception while rendering component 'tableSort' (org.olat.core.gui.components.table.TableSort) listener:[]<br />Message of exception: Index: 6, Size: 1
>>> stack of 1.cause::org.olat.core.logging.OLATRuntimeException: exception while rendering component 'tableSort' (org.olat.core.gui.components.table.TableSort) listener:[]<br />Message of exception: Index: 6, Size: 1
-> at org.olat.core.gui.components.Window.handleDirties(Window.java:994)
   at org.olat.core.gui.components.Window.dispatchRequest(Window.java:455)
   at org.olat.core.gui.components.Window.doDispatchRequest(Window.java:234)
   at org.olat.core.gui.components.AbstractComponent.dispatchRequest(AbstractComponent.java:193)
   at org.olat.dispatcher.AuthenticatedDispatcher.processValidDispatchURI(AuthenticatedDispatcher.java:298)
   at org.olat.dispatcher.AuthenticatedDispatcher.execute(AuthenticatedDispatcher.java:216)
   at org.olat.core.servlets.OpenOLATServlet.executeUserRequest(OpenOLATServlet.java:289)
   at org.olat.core.servlets.OpenOLATServlet.doPost(OpenOLATServlet.java:232)
   at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
   at org.olat.core.servlets.OpenOLATServlet.service(OpenOLATServlet.java:175)
   at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
>>> stack of 2.cause::java.lang.IndexOutOfBoundsException: Index: 6, Size: 1
-> at java.util.ArrayList.rangeCheck(ArrayList.java:653)
   at java.util.ArrayList.get(ArrayList.java:429)
   at org.olat.core.gui.components.table.Table.getColumnDescriptor(Table.java:174)
   at org.olat.core.gui.components.table.Table.getCurrentlySortedColumnDescriptor(Table.java:189)
   at org.olat.core.gui.components.table.TableSortRenderer.render(TableSortRenderer.java:56)
   at org.olat.core.gui.render.Renderer.render(Renderer.java:236)
   at org.olat.core.gui.render.Renderer.render(Renderer.java:186)
   at org.olat.core.gui.components.Window.handleDirties(Window.java:980)
   at org.olat.core.gui.components.Window.dispatchRequest(Window.java:455)
   at org.olat.core.gui.components.Window.doDispatchRequest(Window.java:234)
   at org.olat.core.gui.components.AbstractComponent.dispatchRequest(AbstractComponent.java:193)