Displaying Container element in send mail

Hi Experts,

I am a beginner in SAP Workflows. I have created a simple wokflow in which a mail is sent to a particular user.The workflow is triggered whenever a complaint (BUS20000120)is raised.Now I want to display values of certain container elements in the workflow.I have also created a container element based on BUS20000120. But every time I use some or the other container element attributes, in the mail it is displayed '<BONmae>.<Attributename> not found.

I am not getting any solution to this problem.Please help me.....