connection logging dtrace probe

I whipped up a quick dtrace probe for one of our servers to monitor connection
attempts. My goal was to monitor for any connection attempts from a specific
role within the database. Unfortunatly you can't set logging of connections
for a specific user, and logging all connections on that machine would be
quite the logfile bloater... enter dtrace. With the probe, I can do something
like this:

-bash-3.00$ /opt/csw/bin/sudo dtrace -n 'postgresql*:::connection
{printf("connection attempt: %s@%s\n",copyinstr(arg0),copyinstr(arg1)) }' |
grep robert
dtrace: description 'postgresql*:::connection ' matched 5 probes
2 18984 ServerLoop:connection connection attempt: robert@robert
2 16222 ServerLoop:connection connection attempt: robert@robert
1 16876 ServerLoop:connection connection attempt: robert@pagila

which can be piped to logfile or whatever. I'm attaching a patch against 8.4
as an idea of what I've implemented (actual implementation was against a
custom build) but should be close to working (don't have a working pg repo on
any solaris machines atm). Any feedback appreciated (mostly wondering about
probe name or location). TIA

--
Robert Treat
Conjecture: http://www.xzilla.net
Consulting: http://www.omniti.com