time keeping software (PHP open source if possible)

Some time ago we tried to write our own timekeeping software to log the working hours of all our staff.  We tried using VBA in conjunction with an access database, but never got it to a working standard.

Now we are back on the hunt for some simple php / mysql type system that will allow staff to clock in / clock out to record their working horus, not project specific, just number of hours a week worked.

This may be our first opportunity to write some code and release it back to the community, but we dont want to waste our efforts if there is an established solution out there.

I’ve looked, but cannt find any basic time keeping software.  If you know of anything, or suggestions of where to look, please feel free to leave a comment.

So far, I’ve googled it, but got nowhere.  Looking on source forge:

http://sourceforge.net/projects/phppunchmachine/

this looks like a possible contender, as long as we rewrite it in english.

any comments?