renderConfluenceMacro seems to render content "out-of-context"

Using the workaround for rendered User-Macros as proposed in CONF-3887 and CONF-2293 there comes up a new issue: renderConfluenceMacro won't render the Wiki-Content in the current context. So the following macro will produce two different results:

User Macro:
------------------------------
#set($wiki="

{blog-posts:3|content=titles}")
#set($globalHelper=$action.getGlobalHelper())
#set($renderer=$globalHelper.getWikiStyleRenderer())
#set($context=$content.toPageContext())
#set($xhtml1=$renderer.convertWikiToXHtml($context, $wiki))
#set($xhtml2=$globalHelper.renderConfluenceMacro($wiki))
<dl>
<dt>Version 1</dt>
<dd>${xhtml1}</dd>
<dt>Version 2</dt>
<dd>${xhtml2}</dd>
</dl>
----------------------------

While Version 1 correctly lists the news of the current space Version 2 renders the {blog-posts}

-macro as if it got previewed in a Global Template, i. e. at least not with the News of the current space. It would be great if renderConfluenceMacro would render this correctly as the rendered macros will then shrink to:

#set($wiki=$body)
#set($globalHelper=$action.getGlobalHelper())
#set($xhtml=$globalHelper.renderConfluenceMacro($wiki))
${xhtml}

instead of

#set($wiki=$body)
#set($globalHelper=$action.getGlobalHelper())
#set($renderer=$globalHelper.getWikiStyleRenderer())
#set($context=$content.toPageContext())
#set($xhtml=$renderer.convertWikiToXHtml($context, $wiki))
${xhtml}

which in addition produces a failure when previewed in the Global Templates.