Problem Description:

According to http://www.zkoss.org/product/zkspreadsheet (under "Functionality Highlights), Spreadsheet supports "named range" feature.
But I found I cannot create a named range within Spreadsheet.

Reproducing Steps:

1. select a range of cells
2. click address, try to enter a name to name the range.

Expected:
I can enter a name

Actual:

The address input box doesn't accept any input except deletion.