You will have to use some javascript. the following works.
<HEAD>
<SCRIPT language="javascript">
function submited()
{
if ( document.thisform.buttonclicked.value != "Y" )
{
return false
}
else
{
return true
}
}
function clicked()
{
document.thisform.buttonclicked.value="Y"
document.thisform.action="target.php"
document.thisform.submit=true
}
</SCRIPT>
</HEAD>
<BODY>
<FORM onsubmit="return submited()" name="thisform" method="post">
<INPUT type="text" size="30" name="testbox1">
<P>
<INPUT type="hidden" name="buttonclicked" value="N">
<INPUT type="submit" value="Submit" onclick="clicked()">
</FORM>
</BODY>
if you enter some text into the text box and hit return it ignores it due to the hidden value being set to N but when the submit button is clicked the action target is set and the hidden value changed to Y.
Mark.
