Eclipse output encoding

I notice that output produced with the Eclipse transform (eclipse/eclipse.xsl) contains this line:

<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">

Is ISO-8859-1 a requirement of Eclipse, or can I change this to produce UTF-8?
I tried this in my customization layer, to no effect:

<xsl:output method="html" encoding="utf-8" indent="no"/>

Thanks.