yea... I need one for my MacBook as well. The one I have is shot. It stays in sleep mode for 1 day tops on a full charge... Strangely enough though, after a full charge, I can get a good 3 hours. The sleep mode, is what perplexes me about it.
"Fix it 'til it Breaks."

Jacob - EiC & Director of Technology
Mac Pro Quad 2.66 - 4GB RAM
160 GB SATA RAID 1 - 650 GB Storage
Quad 19" Widescreen LCDs
Accessorized to the Hilt