Basedir property in archetype:generate cannot be overriden

Following is the output when trying to execute archetype:generate using alternative directory for basedir

D:\tmp>mvn -o -npr archetype:generate -Dbasedir=d:/foo
....
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating OldArchetype: maven-archetype-quickstart:RELEASE
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: test
[INFO] Parameter: packageName, Value: test
[INFO] Parameter: package, Value: test
[INFO] Parameter: artifactId, Value: test
[INFO] Parameter: basedir, Value: D:\tmp
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] ********************* End of debug info from resources from generated POM ***********************
[INFO] OldArchetype created in dir: D:\tmp\test
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 8 seconds
[INFO] Finished at: Fri Apr 16 10:53:06 EEST 2010
[INFO] Final Memory: 10M/19M
[INFO] ------------------------------------------------------------------------