This option should contain a comma separated list of container/panel names. These names are then matched agains the other container options. This option can only be used when theme is set to advanced and when the theme_advanced_layout_manager option is set to the value of "RowLayout".
Example of usage of the theme_advanced_containers option:
tinyMCE.init({
...
theme_advanced_containers : "mycontainer1,mycontainer2"
});