GRUB and VESA Bug

Hello!

I've found out that GRUB doesn't set a VESA mode, even if this is set to 
required in the flags.
My kernel told me that the 11th bit in the flags wasn't set and the 
vbe_mode, vbe_mode_info and vbe_control_info fields contained nothing. 
Here is the kernel's output:

nanocore-0.0.1pre-deca
Checking bootloader presence... OK
Checking memory... OK
Checking CPU... AuthenticAMD
Debug... You have enabled the debug mode!
Debug... Checking system call interface... OK
Debug... Kernel heap from c00000 to cfffff
Debug... Multiboot header is at 2c8a0
Debug... I am located at (fd0)/nanocore.dnc
Debug... I've been told to use 0 modules.
Debug... My favourite bootloader is GNU GRUB 0.97
Debug... My flags are 3c7
Debug... My VESA VBE mode is 0 and MI 0 and C 0

Can you help me?

Best regards,

Clemens Brust.