In the templates, the html5 doctype is defined:
<!DOCTYPE html>
Somehow EPrints mangles this back to
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
e.g. http://data.uel.ac.uk/12/
I think this can then cause issues in IE, when combined with the
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
tag.