But this seems all a bit just too easy. so I'd be really thankful for your comments.
It would be even easier to use column header substitution and retain the built-in sort functionality (although this includes the sort direction image bug).
<table id="myDomId"> <thead><tr> <th>#1#</th> <th>#2#</th> <th>#3#</th> </tr></thead>
I tried your suggestion, but now the table headers is not rendered at all. I guess it depends on the template type. Mine is "Named Column (row template)" where you define the <thead> in the section " Before first and after last row text" (APEX 4.2)
On the weekend I will build a testcase, to give you an impression of how it looks like now.
My concern about my solution: Sometimes I have read, some build-in apex background functions should't be used on their own. E.g. what happenes after an Apex-upgrade? I don't want to have to monitor this always. (But this certainly touches a very general issue, and I am not yet that much of an experienced APEX pro.)