
The problem exists because there is no true free X-Browser wysiwyg editor available.

This is something the Mambo developers have no control over - there focus is mambo core development (not development of a wysiwyg editor).
They have tried to accomodate this wish by allowing easier integration of any wysiwyg editor into Mambo.
Htmlarea 3 will be great once it becomes stable, but it is still in development and testing phase.
The other solution is to buy a commercial wysiwyg editor that is fully x-browser capable.