I have a lab setup with 612s, 4.0.9 image. No preposition. Two central servers, one 2000 server and one 2003 server. Client is win xp at branch site. Transfering the same file from both server. Looks like the optimization is working from the 2000 server (a 13MB file takes about 1-2s), but not from the 2003 server (same file 25s). What could be the reasons?