There is an HTML opening tag missing on the default auto-generated login page. Newer browsers don't choke on it as the form and table closes right after it, but some of the older ones do and will splay the form all over the place. Even if they don't its poorly formed. The tag in question is a missing table row opening tag, <tr>, in login form that fails to match to the closing tag for the last row in the form.
Code:
<form action="https://cp.yourdomain.com:8443/psoft/servlet/psoft.hsphere.CP" method="POST">
<input type="hidden" name="action" value="login">
<input type="hidden" name="ftemplate" value="design/login.html">
<tr>
<td><font color="#000080">Login</font></td>
<td colspan=2 align="center"><input type="text" name="login" size="20"></td>
</tr>
<tr>
<td><font color="#000080">Password</font> </td>
<td><input type="password" name="password" size="20"></td>
</tr>
<!--- Missing '<tr>' tag --->
<td colspan=2 align="center"><input type="image" border="0" src="images/login.gif" width="99" height="22" alt=""></td>
</tr>
</form>