[TxMt] Search results sometimes incomplete on first run

I've noticed this issue quite a few times recently.

For one project I work on, I open textmate from cmdline, using "mate <projectdir>"

I then search my codebase for some keyword, and it returns a bunch of results. Looking at the results though, I see they are not complete in that some files are definitely missing from the results.

At this stage (without closing the dialog from the previous run, or changing any search terms), I click the Find button again. TM searches once again, but this time it shows much more matches.

Its occurring quite often, but not every time, and I cant reproduce it at will. I *think* Ive only ever seen on the first search after launching TM

Any idea what is happening here?