problems with h/w multitasking

[aks]

hi

i am preparing a prototype OS.
i am having a problem with hardware multitasking using tss.
basically what i have done uptil now is :

boot loader
enabled a20
protected mode
paging
initialized pic
enabled interrupts

now what i have done is created 2 GDT entries for 2 tasks.
i load the first task using ltr which works fine
now when i switch to the 2nd task using statement "jmp 40:0"
(GDT entry location 40 for task2) the VMWARE i am using crashes.
plz help

also after i set the interrupts using "sti" every time i give a "jmp $"
or an infinite loop i am getting a general protection fault.

[common]

Is this the 6th entry?  Are you performing segmentation?  Where did you enable paging?