Default mimetype for WFS 2.0 responses should be "application/gml+xml; version=3.2" not "text/xml; subtype=gml/3.2". Unfortunately the WFS 2.0. standards has contradictory information with the latter in the UML diagram in Figure 14 but the former in the Table 15. However, recent emails on the OGC WFS/FES email list (unfortunately only accessible to members at
https://lists.opengeospatial.org/mailman/private/wfs-fes.swg/2015-February/000319.html - https://lists.opengeospatial.org/mailman/private/wfs-fes.swg/2015-February/000319.html) have confirmed that the UML diagram is wrong and that "application/gml+xml; version=3.2" is correct.
Although this probably doesn't bother any real clients <img class="emoticon" src="https://jira.codehaus.org/images/icons/emoticons/help_16.gif" height="16" width="16" align="absmiddle" alt="" border="0"/> it causes the current OGC Teamengine WFS 2.0.0 tests to fail (https://github.com/opengeospatial/ets-wfs20 - https://github.com/opengeospatial/ets-wfs20) which gets in the way of other tests of the WFS 2.0.0 service as well.
(The situation is a bit more complicated in that the actual failure during the Teamengine test is that the com.sun.jersey.core.header.HttpHeaderReader from jersey-core-1.18.1.jar can't parse the "text/xml; subtype=gml/3.2" in the Content-Type header because it doesn't expect a "/" in the subtype parameter value. I'm not sure whether that is a bug in jersey-core or whether it is illegal to put a / in a mimetype parameter value but OGC does have such mimetypes defined in other standards!)
CodeHaus Comment From: bgsmase - Time: Wed, 18 Feb 2015 02:57:53 -0600
<p>Ah, I didn't spot <a href="https://jira.codehaus.org/browse/GEOS-4011" title="Unquoded subtype=gml/<version> breaks HTTP/1.1 standard" class="issue-link" data-issue-key="GEOS-4011">GEOS-4011</a>, very interesting. I was going to look for the rules on allowed characters in HTTP headers next and see if the OGC had specified some illegal mimetypes. At least for WFS 2.0 we can say that the "application/gml+xml; version=3.2" HTTP legal version is also the intended OGC version. </p>