Hmm...lots of choice. Not sure this will work on 3.x, but worth a shot.
(1)Snapshot
(2)copy the RAM:disk.info file to ENVARC:Sys/def_ramdisk.info
#6
and then you need to add the following to your user-startup :
makelink RAM:disk.info ENVARC:SYS/def_RAM.info soft
