textbox Value not saving in outlook 2003 cutom form

dear all,
I have a custom form in outlook 2003.
Using vb script i populate the textbox.I can see the text box is populated. but when i save and close and reload the form for the second time it is not showing the value in textbox .instead it is blank

I there any way to store the values in the form

note: textbox readonly, multiline