You can now create groups on secondary domains.

Release track:
Rapid & Scheduled

Editions included:
Google Apps, Google Apps for Business, Government and Education

Languages included:
US English only (Next Generation Control Panel)

How to access what's new:
In the Administrator Control Panel, go to ‘Groups,’ select ‘Create a new group,’ and choose the desired domain name from the dropdown menu under ‘Group email address.’

For more information:
http://www.google.com/support/a/bin/answer.py?hl=en&answer=33343&topic=25840

whatsnew.googleapps.com
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