Sharing single build file among multiple destributed agents

Hello,
I am not sure if this question has already been asked and answared or not.

I have installed multiple build agents and a default build agent on server, Is it possible to share a single nant build file among those destributed agents?

In configuration file I specified build file path as %system.agent.home.dir%/default.build

when the build task submitted in those build agents, I got an error as "Cannot find build file by path specified in build configuration settings: 'C:\BuildAgent\default.build'"...

But it is working when I submit the build in the server agent.

I am using NAnt as build tool

Another question
     Will I have to install NAnt in all agents?


Thanks
Maniruzzaman.