[Erwin]

Oh.... if you already have the Preview PM hack installed, then all you have to do to make that work with my hack is this:

In your privmsg template:

Find this:

<form action="private.php" method="post" enctype="multipart/form-data" name="vbform" onSubmit="return validate(this)">

Add this underneath:

<input type="hidden" name="prevmessageid" value="$privatemessageid">

Then find this:

<input type="submit" class="bginput" name="submit" value="Send Message" accesskey="s" tabindex="4">

Add this underneath:

<input type="submit" class="bginput" name="preview" value="Preview Message" accesskey="p" tabindex="4">

The preview function should work immediately. From what I can remember anyway.