You should see this error message somewhere in the log (at beginning)
[Thu Nov 17 20:53:45 2011] ERROR: [scf-00148] Consistency Group snapshot is not supported with the META_DATA_VOLUME option
Snap Creator does not support CG snapshots using the META_DATA_VOLUME option at this time. This is something we are working on but due to complexity was not something we could solve easily.
The only reason you would need CG snapshot for oracle is if you are using ASM and if you cant use SnapDrive. If this is case you would need to build two config files one for logs and one for data and for logs use ARCHIVE_LOG_ONLY option. Otherwise simply dont use CG you dont need it.