Installed reFIT on Lion and now I can't login
If you disable journaling for the Macintosh partition (in order to access files from within Linux) this should work:


hold &#x2325; upon boot
select Recovery HD OR boot from Mac install DVD/USB 
open Disk Utility. Select Macintosh HD. Hold &#x2325; and click on File. Select Disable Journaling.
boot from a Linux Live CD. Open root terminal.
delete /Library/StartupItems/rEFItBlesser on the Mac partition
delete /efi on the Mac partition


If journaling was already disabled on the Mac Partition, move to step 4.