RedHat Linux 6.2 and memory

Hi Gang,
Installed RedHat Linux 6.2 with no trouble. Lilo is functioning from the

boot partition and have added the line append="mem=128m" and the
beginning. All the memory that is seen is 64mb. Win98 and SuSE 6.2
see the 128mb. What needs to be done so that RH see the 128mb?
TIA
Clay Stapleton