We'll use:
$USER to stand for the UNIX username that should be clear from context
$USERPATH to stand for the first letter of the username, a slash, the next two letters of the username, a slash, and the username, concatenated. For example, a $USER of "adamc" would have $USERPATH be "a/ad/adamc".
$DOMTOOL to stand for /afs/hcoop.net/common/etc/domtool, the root of global DomTool data