Tab problem with highlighting default text of multi-line textfield

I have a form designed with LiveCycle Designer 8 in which I have several one-line text fields and a multi-line text field. I have set default text values for each, such as "[insert something here]". I have also set the tab order. However, when tabbing, the default text is highlighted on the single-line textfields but the cursor goes to the end of the default text on the multi-line field and does not highlight the default text as it does on the single-line text field. Is this a bug or am I missing something here? Need to have the default text on the multi-line field highlighted so when the user tabs into it, when they begin typing, it will delete the default text as it does on a single-line text field. Thanks in advance for your expert advice.