I noticed something earlier today on a wiki outside Wikimedia servers and thought it might just be a problem there, but with the help of kylu, I tested it on Meta and confirmed it doesn't work on Wikimedia wikis either.

Compare:
http://meta.wikimedia.org/w/index.php?title=Special:NewPages&hidebots=0&namespace=4&username=User%3AKylu

to

http://meta.wikimedia.org/w/index.php?limit=2&title=Special%3AContributions&contribs=user&target=Kylu&namespace=4&year=2008&month=10

Kylu flagged herself as a bot to perform this test and made the page and it indeed did not show as one would expect.

Version: 1.14.x
Severity: normal
URL: http://meta.wikimedia.org/w/index.php?title=Special:NewPages&hidebots=0&namespace=4&username=User%3AKylu