return value to activex

hi
i try to set the captio of a button while setting the <param name..
. But it doesn´t work. here is my code. thaks for help!

eric

Const constBtnCaption = "CONST"
Public mButtonCaption As String
'Public ButtoAs String
Option Explicit

Public Sub UserDocument_ReadProperties(PropBag As PropertyBag)
myBtnCaption = PropBag.ReadProperty("ButtonCaption", constBtnCaption)
End Sub

Public Property Get ButtonCaption() As String
ButtonCaption = myBtnCaption
End Property

Public Property Let ButtonCaption(ByVal NewButtoncaption As String)
ButtonCaption = NewButtoncaption
PropertyChanged "ButtonCaption"
End Property

Private Sub Command1_Click()
Command1.Caption = myBtnCaption
End Sub

'HTML

<HTML>
<HEAD>
<TITLE>Projekt1.CAB</TITLE>
</HEAD>
<BODY>
<OBJECT ID="UserControl1"
CLASSID="CLSID:A64D3A24-79BA-4F68-813A-D3BFAFA893CF"
CODEBASE="Projekt1.ocx">
<PARAM NAME="ButtonCaption" VALUE="yeah">
</OBJECT>
</BODY>
</HTML>