Usb Mass Storage

Is it possible to have this function on symbnian phones like n91 does? somhow in think it can be done for innstance the original motorola e398 does not work as USB mass storage(plug and play) but with some modifications to it by modifying it's firmware; which is the only way software apart from java programs can be installed in it, using some user created packages ( monster packs or flex). Thereby adding this feature to it (for more info check motomodders.net oer http://e398essentials.wikispaces.org). The current symbian framework allows for softwares to be installed in it unlike the e398 therefore there wouldn't be any need for modifications to the firmware.
The question i pose to software developers is why there seem to be no effort in making this software. To me i think users who use their devices as mp3 players and others that use theirs as storing personal files, will find tyhis function indispensable, i personally would not hesitate to purchase such a software if it was available. The drive of having to installl drivers sounds and looks too cumbersome and hinders that mobility edge