I think it's safe to conclude, at the moment of this writing, that this technique is, or has become, unsupported.
A better approach would to work with 2 different displays: one design for desktop readers, and one for mobile readers, as demonstrated below (tested, and works):
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<style type="text/css">
<!--
.ReadMsgBody {
width: 100%;
}
.ExternalClass {
width: 100%;
}
a:hover,
a:visited,
a:active {
color: #ffffff;
}
@media screen and (max-width: 480px), screen and (max-device-width: 480px) {
body { -webkit-text-size-adjust: none;}
div[id=desktop] {
display:none !important;
width:0px !important;
overflow:hidden !important;
}
div[id=mobile] {
display:block !important;
width:100% !important;
height:auto !important;
max-height:inherit !important;
overflow:visible !important;
}
div[id=mobile] table{
display: block !important;
overflow: auto;
}
div[id=mobile] img{
width: 100%;
}
-->
</style>
<style type="text/css">
div.online p {margin:0; padding:0; margin-bottom:0;}
div.online a:link, div.online a:visited, div.online a:hover, div.online a:active { color: #333333; }
</style>
</head>
<body bgcolor="#e6e6e6" style="margin:0;">
<div class="online" style="margin:10px auto; color: #333333; font-family: verdana; font-size:11px;text-align:center;">
<a href="http://somedomain.com/some/page.htm?lang=nl" target="_blank" style="text-decoration: none; color: #333333;">View in browser</a>
</div>
<div id="desktop">
<table cellpadding="10" cellspacing="0" border="0" style="width:100%; background-color:#e6e6e6;">
<tr>
<td align="center">
<table cellpadding="0" cellspacing="0" border="0" style="width:620px; background-color:#ffffff; text-align:left;">
<tr>
<td>
<table cellpadding="0" cellspacing="20" border="0" style="width:620px; text-align:left; background-color:#ffffff;">
<tr>
<td><a href="#" target="_blank"><img src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/header.jpg" border="0" style="display:block;" /></a></td>
</tr>
</table>
</td>
</tr>
<tr>
<td>
<table cellpadding="0" cellspacing="20" border="0">
<tr>
<td valign="top"><img src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/00f_1.gif" style="max-width: 240px;" /></td>
<td valign="top">
<table cellpadding="0" cellspacing="0" border="0" style="font-family:Arial, Helvetica, sans-serif; font-size:12px; color:#333333;">
<tr>
<td style="font-size:22px; color:#fea900;">Block 1</td>
</tr>
<tr>
<td><img src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/filler12.png" /></td>
</tr>
<tr>
<td>Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?</td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
<tr>
<td>
<table cellpadding="0" cellspacing="20" border="0">
<tr>
<td valign="top"><img src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/0f0_1.gif" style="max-width: 240px;" /></td>
<td valign="top">
<table cellpadding="0" cellspacing="0" border="0" style="font-family:Arial, Helvetica, sans-serif; font-size:12px; color:#333333;">
<tr>
<td style="font-size:22px; color:#fea900;">Block 2</td>
</tr>
<tr>
<td><img src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/filler12.png" /></td>
</tr>
<tr>
<td>Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?</td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
<tr>
<td align="center" style="border-bottom: 2px dotted #666666;"><img src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/filler12.png" /></td>
</tr>
</table>
</td>
</tr>
</table>
</div>
<div id="mobile" style="display:none; width:0px; max-height:0px; overflow:hidden;">
<table cellpadding="10" cellspacing="0" border="0" style="width:100%; background-color:#e6e6e6; display:none;">
<tr>
<td align="center">
<table cellpadding="0" cellspacing="0" border="0" style="width:100%; background-color:#ffffff; text-align:left; display:none;">
<tr>
<td>
<table cellpadding="0" cellspacing="0" border="0" style="width:100%; text-align:left; background-color:#ffffff; display:none;">
<tr>
<td><a href="#" target="_blank"><img id="header" src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/header.jpg" border="0" style="display:block;" /></a></td>
</tr>
</table>
</td>
</tr>
<tr>
<td>
<table cellpadding="0" cellspacing="10" border="0" style="display:none;">
<tr>
<td>
<table cellpadding="0" cellspacing="10" border="0" style="font-family:Arial; font-size:14px; color:#333333; display:none;">
<tr>
<td><img src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/00f_1.gif" /></td>
</tr>
<tr>
<td style="font-size:20px; color:#fea900;">Block 1</td>
</tr>
<tr>
<td>Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?</td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
<tr>
<td>
<table cellpadding="0" cellspacing="10" border="0" style="display:none;">
<tr>
<td>
<table cellpadding="0" cellspacing="10" border="0" style="font-family:Arial; font-size:14px; color:#333333; display:none;">
<tr>
<td><img src="https://www.domain.com/x-http://somedomain.com/some/page/img/props/0f0_1.gif" /></td>
</tr>
<tr>
<td style="font-size:20px; color:#fea900;">Block 2</td>
</tr>
<tr>
<td>Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?</td>
</tr>
</table>
</td>
</tr>
</table>
</td>
</tr>
<tr>
<td align="center" style="border-bottom: 2px dotted #666666;"> </td>
</tr>
</table>
</td>
</tr>
</table>
</div>
<div class="online" style="margin: 10px auto 25px; color: #333333; font-family: verdana; font-size:11px;text-align:center;">
<p align="center">
<a href="http://somedomain.com/some/page.htm?lang=nl" target="_blank" style="text-decoration: none; color: #333333;">Unsubscribe</a> -
<a href="http://somedomain.com/some/page.htm?lang=nl" target="_blank" style="text-decoration: none; color: #333333;">Edit profile</a>
</p>
<p align="center" style="margin-top: 15px;"></p>
</div>
</body>
</html>