I seem to have a problem with the confirmation email: This

I seem to have a problem with the confirmation email:

This seems to include the HTML tags as part of the text for example this has been received:

<p>Thank you for signing up to our upcoming event. </p>
<p>We have included the details below and are looking forward to seeing you then.</p>
<p>[Twickenham Action Day]</p>
<p>Start time: [8 June 2013 11:00 am]</p>
<p>End time: [8 June 2013 4:00 pm]</p>
<p>[<h2>Twickenham Action Day - Saturday 8th June (11am - 4pm)</h2>
<p>Get involved with our regular campaigning days in Twickenham, with delivery, door knocking and recruitment to do there is something for everyone.</p>
<p>Starting at 11am we stop for lunch at a local pub between 1-2pm before another campaigning session until 4pm.</p>
<p>Location: TBC (Twickenham constituency)</p>
<p>Just ask if you have any questions.</p>]</p>
<p>[Twickenham and Richmond Lib Dems]</p>