Dual lan connections jumbo/std

Hi. I have a question about XBMC's library function... I don't know if it's possible to do this, my situation is this.. I have a dual network setup - one with jumbo frames used for nfs and samba sharing and one with standard mtu for everything else. My jumbo net is 10.0.2.x and the standard mtu is 10.0.1.x. I've mounted the nfs share on the jumbo-net to a folder on my htpc. The problem is that if I scan that folder to my mysql-server and start playing something all traffic seems to be routed through the standard mtu net. Am I misunderstanding something? The sql-entries just seem to point to my mounted folder, and since it's mounted through the jumbo net, shouldn't a movie played from that folder go through the jumbo net? I can reach both nets fine and network-wise everything seems to work as intended..
I don't really know if it's something in xbmc that's causing this or if it's the guy behind the keyboard
Anyway.. Thanks for the great work with XBMC!