If I make immediate='true', that will work.
Check if there are any messages for validation errors generated.
Else if I remove rich:column, delete button works, even though some script error occured.
What is RF version?
I appreciate your helping attitude, Nick. Fortunately I am able to correct the issue. Basically I was also using selection attribute of orderinglist and it binds to a list in backing bean. When I changed that to Set, it worked.