error while accessing menus in Runtime workbench from SLD

Hi I am getting following error while accessing menus in runtime workbench from SLD.( example: SLD->runtime workbench->component monitorung ->display)

"Error during communication with System Landscape Directory: User credentials are invalid or user is denied access "

I am using PISUPER to login to SLD and i am able to login to XI using this ID. I could find role -SAP_XI_RWB_SERV_USER - also in the user id profile of PISUPER.