Clarifications on IBM RTC - Ant Task

I am using RTC’s ANT task <teamLastModified> to fetch last modified timestamp.

http://pic.dhe.ibm.com/infocenter/rtczhelp/v2r0m0/index.jsp?topic=/com.ibm.team.build.doc/topics/r_ant-tasks.html

Managing change and releases > Building with Jazz Team Build > Jazz build Ant task reference > Working with Jazz source control > teamLastModified

Our implementation is same as example given above path. However when we execute on same stream, two instances have given two different result. My understanding is that the last modified timestamp is from Stream from which workspace is created. However, comparing the files, I notice differences in timestamp (only at minutes, seconds & milliseconds level).

Questions are:

1.       <teamLastModified> to fetch last modified timestamp from local workspace / Repository workspace / Stream?

2.       How can we get a consistent time stamp of last modified changes from a stream?