Prerequisites:
- QuickBuild build agent 5.0.29 is installed on Mac OS X 10.8 Mountain Lion;
- agent.sh is updated with RUN_AS_USER="svcbuildm";
- the machine is rebooted.

Result:
After the reboot System Attributes tab displays the environment:
PATH /usr/bin:/bin:/usr/sbin:/sbin

'echo $PATH' in the shell displays:
/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/opt/bullseye/bin:.:/Builds/QuickBuild/buildagent/bin:/Applications/Xcode.app/Contents/Developer/usr/subversion-1.6/bin:/Users/svcbuildm

Expected result:
The shell's PATH setting is expected instead of the one displayed.

Conclusion:
Shell's PATH environment is not preserved in QuickBuild build agent as expected.

NOTE: This behavior is not seen on earlier Mac OS X 10.6 and 10.7.