How long can I store cell lysis buffer at 4C for? - (Jan/21/2013 )

Is it possible to keep the lysis buffer (containing protease + phosphatase inhibitors) for more than a week?
How long (if any) does it take for these inhibitors to degrade?

Some of these inhibitors will degrade very rapidly (can't recall which ones specifically atm), so storage in the liquid form for more than a week is not a good idea. You can store frozen inhibitors for up to about 6 months and lysis buffer without inhibitors for a similar period at 4 deg C.