Use full Ram in LPC1837 (Cortex-M3)

I am using LPC1837 (Cortex-M3) controller in my Project.and Keil version 4.60
LPC1837 has three Ram Partitions as follows.

32kb at 0x10000000
40kb at 0x10080000 and
64kb at 0x20000000

But in keil 4.60 Target option there are only two places for on-chip Ram Memory as
IRAM1 and IRAM2 ,where i am mensioning 40 kb and 64 kb partition.

Can any one tell me how to use Full Ram memory.
Thanks in Advance.

-- Manas --