Voip and load-sharing per-packet

I have two routers 1760 which connect together via two T1s with load-sharing per-packet option. The documentation says that this may cause problem with VOIP because of arriving-disorderedly packets.

In my case, I do have some phones using voip. These phones are on one side connecting to the phone server on the other side.

Is it possible to specify all connections to a specific ip address ( the address of the phone server ) not to use load-sharing per-packet options ?

Thanks for your advice,

DT