Due to a bug in echo2, focus traversal is not restricted to the fields on modal dialogs.
The focus can be moved from a modal dialog to the parent form, as described here: http://forum.nextapp.com/forum/index.php?showtopic=2181
A potential workaround is described here: http://forum.nextapp.com/forum/index.php?s=&showtopic=2181&view=findpost&p=10409
"A second, possibly better idea is to have onfocus handlers on components that call a to-be-written "verifyFocus()" method in the ClientEngine and if they aren't eligible for focus, they would prevent the event. I'm not sure if preventing the even tdefault will result in the element being skipped (guessing it won't). So we'd need to have some code that found the next focusable element by walking the tree and looking at tabindex values and then explicitly calling focus() on the appropriate element (not fun, but doable). We'd also provide a default focus handler that could be registered on elements so each JS module would not need to provide its own if it otherwise did not care about focus events."