When using the CVS plugin to checkout I see it doesn't use the same timestamps for checkout as for rlog:
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17:48:40 Started by user testadmin
17:48:40 [EnvInject] - Loading node environment variables.
17:48:40 Building on master in workspace /var/lib/jenkins/jobs/test_checkout/workspace
17:48:42 cvs checkout -f -P -r test_branch -D 18 Dec 2013 17:48:42 +0100 -d module1 module1
17:48:52 cvs checkout -f -P -r test_branch -D 18 Dec 2013 17:48:42 +0100 -d module2 module2
17:48:58 cvs checkout -f -P -r test_branch -D 18 Dec 2013 17:48:42 +0100 -d module3 module3
17:49:01 cvs checkout -f -P -r test_branch -D 18 Dec 2013 17:48:42 +0100 -d module4 module4
17:49:15 cvs rlog -S -d18 Dec 2013 17:46:21 +0100<18 Dec 2013 17:48:40 +0100 module1
17:49:17 cvs rlog -S -d18 Dec 2013 17:46:21 +0100<18 Dec 2013 17:48:40 +0100 module2
17:49:19 cvs rlog -S -d18 Dec 2013 17:46:21 +0100<18 Dec 2013 17:48:40 +0100 module3
17:49:20 cvs rlog -S -d18 Dec 2013 17:46:21 +0100<18 Dec 2013 17:48:40 +0100 module4
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The job is started 17:48:40.
The first CVS checkout is done 17:48:42 and all subsequent checkouts uses the 17:48:42 timestamp. Shouldn't they rather use 17:48:40 when the job started?
The rlog is done but now against when the job started and not against the actual checkout.

I've seen a time difference between 1 and 5 seconds, but there is always a difference.