Problem Hibernating in Windows XP

I am having a problem getting my PC to hibernate.
Whenever I startup my computer, I can have my computer hibernate just fine the first time. But if I try to hibernate any other time after that, it goes through the motions (screens blank out) but the hibernate animation never comes up, then it boots back into windows, and I get this Yellow exclamation point in my system tray that says something to the effect of “Insufficent Resources available to complete API”.

I don’t know why that is.
I have an intel P4 2.53Ghz, running windows XP with SP2, 1.5GB of RAM, 2 hard drives (Swap file is on the second hard drive) on an Abit IS7 motherboard.

Any help will be appreciated.