how to create table with merge cell via html

[whoisltd]

I want to create table with merge cell via html. But can't find out how to do that.
rowspan or colspan not work on td tag
Example table:

[JorjMcKie]

If you are sure that you made the correct HTML syntax for your table, then that is all that you can do.
If it is not handled correctly in page.insert_htmlbox() then there is nothing that can be done about it.

The Story object, that is invoked internally, fails to support this. There are indeed limits WRT Story support of HTML / CSS syntax. Roughly it is HTML4 and CSS2, but there are exceptions here and there. Among such examples is no support of text underlining.