Extend the TextArea Component in the lwuit library of J2me. The extended TextArea must behave like the TextArea class but the only difference is that it must allow the user to type in text in the same way that the user would type text into a TextField.
I found the source code for the original TextArea component at:
http://developers.cloudmade.com/repositories/entry/j2me-lib/trunk/CloudMadeMobileProjectBasic/src/com/sun/lwuit/TextArea.java
It is important that you do not alter the lwuit framework. Either create a new component or extend the existing TextArea component.