This page shows that the latest 1.2.x branch of MooTools (1.2.5 at the time of writing) treats the insertion of row data into a tbody differently on Opera/Win to other browsers; specifically, the attributes appear to be stripped from the tr tag. Inserting into a table without a tbody appears to be fine. Tested on:
The 1.3 branch appears to be fine in this respect.
Test passes are in green italic, test fails are in red bold.