cosi:

<script language="JavaScript" src="md5.js"></script>

<form name="login" action="test3.asp" method="POST">
<input name="user" type="text">


<input name="pass" type="password">


<input type="submit" onClick="hex_md5(document.login.pass.value)">
</form>


nn funziona
mi passa i valori in chiaro