Portaudit detects wrong version of subversion

[Mike Clarke]

There appears to be an inconsistency somewhere in my ports. I build all my 
ports from source and don't use pkg add.

curlew:/home/mike% portaudit 
Affected package: subversion-1.7.13
Type of problem: subversion -- multiple vulnerabilities.
Reference: 
http://portaudit.FreeBSD.org/e3244a7b-5603-11e3-878d-20cf30e32f6d.html

1 problem(s) in your installed packages found.

You are advised to update or deinstall the affected package(s) immediately.

But I'm running version subversion-1.8.5, not subversion-1.7.13

curlew:/home/mike% svn --version --quiet
1.8.5

And there's no sign of any other version on my system

curlew:/home/mike% pkg info -x subversion
subversion-1.8.5

Although portaudit reports a problem everything looks OK with pkg audit

curlew:/home/mike% pkg audit
0 problem(s) in the installed packages found.

Where should I be looking to clean up this inconsistency?

-- 
Mike Clarke