Username is completely ignored

When I run something like "mvn release:prepare -DdryRun=true -Dusername=mb011000", the resulting contents of release.properties suggest that the username is being completely ignored when forming the scm.url:

scm.username=mb011000
scm.url=scm\:cvs\:pserver\:anonymous\:@prdwebdev17\:/projects\:system-core

Note that the "anonymous" has stuck around for some reason. This may be related to MRELEASE-83 and/or MRELEASE-107, but I don't think it's a duplicate.