Below are two MWEs. The only difference is with \setupinteraction. When 
the  resulting link is copied from the pdf and pasted into a browser, 
one can see that there is a trailing / added to the interactive version, 
but not to the non-interactive version. For this url (and many others), 
that causes a 404 failure. Additional experimentation shows that a 
second / is not added when a trailing slash has been provided.

This is not the case with TL2013. It is the case with 2014.03.28 15:04 
MKIV beta.

Why has the trailing slash added? Is this an intentional change? If so, 
is there a method to invoke the older behavior.

    \starttext
    \useURL[aurl][http://www.mieleusa.com/manuals_pdf/Residential/Ovens/H387-2_us.pdf]
    \from[aurl]
    \stoptext


    \setupinteraction[state=start]
    \starttext
    \useURL[aurl][http://www.mieleusa.com/manuals_pdf/Residential/Ovens/H387-2_us.pdf]
    \from[aurl]
    \stoptext

-- 
Rik