hphantom (now?) creating whitespace

[pkra]

A follow up of sorts from #220. We have the following in a publication

{\hphantom{mm} {\tt http://homes.cerias.purdue.edu/\~{}ssw/cun/index.html}}.

which used to come out as

The author maintains the latest versions of the tables at <monospace>http://homes.cerias.purdue.edu/s̃sw/cun/index.html</monospace>.

but now comes out as

The author maintains the latest versions of the tables at    <monospace>http://homes.cerias.purdue.edu/s̃sw/cun/index.html</monospace>.

While this is a bad example, I'm wondering in how far this new behavior is desirable, since the added whitespace won't have the desired / any effect.