This is what I find below my ~/.m2:

-rw-r--r-- 1 x x  711693 2011-05-02 14:12 ./org/mvel/mvel2/2.1-SNAPSHOT/mvel2-2.1-20110501.033205-24.jar
-rw-r--r-- 1 x x  711693 2011-05-02 14:12 ./org/mvel/mvel2/2.1-SNAPSHOT/mvel2-2.1-SNAPSHOT.jar

At that time I didn't build anything except droolsjbpm/drools, so both must have been downloaded by the same build.

-W