You can't use ODBC in PSQL 2000i from another workstation if you are using Workgroup.  It's been a long time since I looked at it but as I recall, you may have to install the Workgroup engine rather than the client to the station you are trying to connect from which in turn may introduce other Gateway related issues.  
 
If you are using Windows 7, you REALLY should look at upgrading to the current version of Pervasive.  PSQL 11 has much improved ODBC capability and for Workgroup (up to 5 users which you are) it is only $49/user.