File sharing across 2 subnets

[charlestdenver]

I administer a small company network with 2003 sbs as domain controller. We have 2 sites connected thru a TI. The subnet that the server and most of the system is on is 10.0.0.x, and the second subnet is 10.0.1.x. What I'm trying to solve is, any computer on the 10.0.0.x net can read and write to shared files on the 10.0.1.x net. But in revearse computers on the 10.0.1.x net are only given read access to files on the 10.0.0.x net- but can write new files to shared directories on the 10.0.0.x net. I'm thinking this is a setting in group policy but havn't found how to fix it. Any help would be appreciated.

Charles