Catalyst 6506 and 3548xls

[Josh Youngman]

i am attempting to configure a 6506 with and 8prt GBIC i wish to have 2 3548xls uplinked to the 6506 via gigabit.  i am unable to get any of the interfaces on the *new* 3548xls to come up.  i did a no shutdown and it comes up and goes right back down. what am i missing here. even if i simply wanted to use the 3548 standalone and have 48 switched users?  i assumed out of the box the ports would be enabled automatically and come up and be ready to go, what am i missing, thanks