Does
this post linking to an explanation on mobiletechreview as to why there is only 49 available to the user.
"Windows Mobile 5.0 caches operating system files heavily to improve performance, and uses a significant portion of available RAM. At boot, 49.47 megs of RAM are shown as available, and another 19 megs of that available memory are used by the OS. That means you'll have about 30 megs out of 64 available to run programs. That's certainly adequate even for power users, but it's surprising how much of that 64 megs is used by the device."