I think in older versions of dojo (<1.6), you used to be able to pass an onKeyPress function into InlineEditBox's "editorParams" property. But I think in the more recent versions, that was either removed or there's a bug that makes it not work. In recent versions of Dojo, I've added a listener to the "editWidget" of InlineEditBox. I do something like this:
on(eb.wrapperWidget.editWidget, "keypress", function (evt) {
console.log("EVT:", evt);
});
where eb is the InlineEditBox. However, the wrapperWidget isn't created until the first time you click on the InlineEditBox, so I have to provide a sort of hacky way to initialize the wrapperWidget.
eb.edit();
eb.cancel();
There may be a better way in recent versions of Dojo that I haven't seen, but this is a solution that works. To help, I've created a JSFiddle, http://jsfiddle.net/N5WPk/, of this example.