In the JIDE demo "Resize Table Demo", you should how to show/hide columns and there is also the option to resize all columns.
Could you plan to add in this dialog the ability to enter column width? (like in Windows Explorer in the "Choose Details" dialog shown when you right click on the table header and select "More..."). Also if this dialog can be triggered programmatically it would help in making the all features accessible.
thanks,
-fred