java plugin not respecting fork settings

In the Java jelly.plugin, it looks like fork is being set to true in all cases, even when I have maven.compile.fork=no in my project.properties (or my build.properties, or on the command line as a system property). What dumb thing am I doing wrong?

Excerpt:

<j:choose>
<j:when test="$

">
<ant:javac
fork="true"
destdir="$

"
excludes="**/package.html"
debug="$

"
deprecation="$

"
optimize="$

">
<ant:src>
<ant:path refid="maven.compile.src.set"/>
</ant:src>
[snip]
<j:if test="$

">
<ant:setProperty name="fork" value="$

" />
</j:if>
[snip]
</j:choose>

In my case, that ant:setProperty call is not being picked up; fork is apparently always "yes".

Cheers,
Laird (new and enthusiastic Maven user)
–
Laird J. Nelson
Electronic Channel Group, Fidelity eBusiness (Veritude)