[U-Boot] OneNAND operations.

Hello, All! My next question is about OneNAND U-Boot operations. I use U-Boot 2009.08.rc2. There is "onenand" command:

onenand read[.oob] addr off size read/write 'size' bytes starting at offset 'off' to/from memory address 'addr', skipping bad blocks.

Can someone explain me how should I use it please? I try: onenand read 0x80000000 0x00240000 1000 0x80000000 - is the address where data will be put? "off" (I use 0x00240000 becouse I want to read OMAP3's environments) size is 0x1000 - just for example.

And I get:

OneNAND read: offset 0x240000, size 0x1000 0 bytes read: OK

What is wrong? And what is [.oob]?

Thank you!