How to copy LONG column

I need to copy a long varchar from one table to another using

UPDATE tab1 SET longcol = (SELECT longcol2 FROM tab2 WHERE tab1.key=tab2.key);

But I get an error that this is an invalid use of a LONG column. How do I insert or update a long column by copying a value from another column?

Tom Received on Tue May 20 1997 - 00:00:00 CDT