Berechung der ausgabe in neuem Fenster aufgehenlassen?

<form method="GET" action="http://coinmill.com/currency" onsubmit="if (this.currencyamount.value==''){alert('Please enter an amount');return false;}if (this.currencyfrom.selectedIndex==0){alert('Please choose a currency.');return false;}return true;">  
<table border="0" cellpadding="2" cellspacing="0" summary=""><tr><td>  
Amount:</td><td><input type="text" size="8" name="currencyamount">  
</td></tr><tr><td>
From:
</td><td>
<select name="currencyfrom">  
<option value="" selected>Select a currency</option>  
                <option value="EUR">Euro (EUR)</option>  
                <option value="PLN">Polish Zloty (PLN)</option>  
                <option value="USD">United States Dollar (USD)</option>  
</select>
</td></tr><tr><td>
To:
</td><td>
<select name="currencyto">  
<option value="" selected>All other currencies</option>  
             <option value="BTC">Bitcoin (BTC)</option>  
</select>
</td></tr><tr><td>
</td><td>
<input type="submit" value="Convert">  
</td></tr></table>
Currency conversion powered by <a href="http://coinmill.com/">coinmill.com</a>  
</form>