Tricking pkg_version

[Luke Dean]

I installed phpbb-3.02 from ports (i.e. "make install").
I then used phpbb's built-in upgrade system to upgrade it to version 3.04.
This of course did not bump the version number in the ports/packages
database.
I frequently use csup + pkg_version -L to spot ports that are out of date,
and this one will probably show up forever now.

I don't wish to recompile anything because I've made a lot of custom
changes to the php code and I don't want to go through the pain of
remerging all that stuff again.

Is there a way that I can tell pkg_version that I think I'm already
running version 3.04?
I'd like to continue to pretend that this package is still managed by the
ports/package system even though I've modified it.  I realize that this is
not sane, but it will help me spot new versions when they become available
and I just like having all my software listed in one place like this.

I've briefly poked around in /var/db/pkg/phpbb-3.0.2, but those files with
all their checksums just scream "don't touch!" to me.

I'm not using any ports/package management tools except for "make" and
"pkg_*", so aside from whatever database pkg_info uses, there are no other
databases to worry about.