Problem sorting datagrid when creating columns programatically

[Dima]

I have a datagrid for which I programatically create the
columns, AutoGenerateColumns is set to false. I'm
creating the columns and setting the sortExpression in
code. However when the sort link (the column heading) is
clicked a post back occurs but does not trigger the sort
event. I've read that this is a problem. Has anyone
found a work around?