Well in theory you need recent kernel that supports ubifs and recent mtd-utils and follow stuff here
http://www.linux-mtd.infradead.org/d...tml#L_usptools
http://www.linux-mtd.infradead.org/doc/ubifs.html

I was trying to mount it too but didn't manage yet. Was also thinking that easier might be to simply flash it to NAND in my beagleboard and mount it there. But there shouldn't be problem with mtdram, just create mtdram device, use ubi tools to create/attach ubi volume and 'flash' image to it.