Emerging mercurial-0.8.1 with asciidoc-7.0.4 fails with ERROR: hg.1.txt: line 7: unsafe: {eval:{"article" .......... Quick fix is to simply add option --unsafe to commandline of asciidoc inside ebuild.
*** Bug 132849 has been marked as a duplicate of this bug. ***
Fixed in dev-util/mercurial-0.9.1-r1 - thanks for reporting.
Apparently mercurial-0.9.3 was stabilized without my knowledge (bug #159856).