autoit3a.exe has encounter a problem and needs to close

Unfortunately my AutoIT application falls over when reading an input
on an IE form which has a value which is null ... such as:

<INPUT TYPE="TEXT" NAME="Data4" SIZE="55" MAXLENGTH="55" VALUE="">

My code snippet is:

$oIE = _IEAttach("Data Form")
$oForm = _IEFormGetObjByName ($oIE, "dataform")
$oText = _IEFormElementGetObjByName ($oForm, "Data4")
MsgBox(0, "Form Element Value", _IEFormElementGetValue ($oText))

and the above snippet works fine if the VALUE="some text" but falls
over if it is null (autoit3a.exe has encounter a problem and needs to
close ...).

I'm running AutoIT at the latest version v3.2.4.9 (I've tried latest
beta v3.2.5.1 too) and I'm using IE version 7.0.5730.11.

Can anyone suggest how I can get workaround or solve this one please?