Changing collation is failing - SQL 2008 R2

I read numerous other posts that indicate how to rebuild system dbs with a new collation. I have no user databases as of yet (vendor noticed it was wrong collation before they started their installation.) They want the collation to be "Latin1_General_CI-AS" instead of "SQL_Latin1_General_CP1_CI-AS".

I have executed this:

Setup /ACTION=REBUILDDATABASE /INSTANCENAME=SQLA /SQLSYSADMINACCOUNTS="domain\acct" /SAPWD=MyPwd!" /SQLCOLLATION="Latin1_General_CI-AS"

This is from my Summary.txt file from myC:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log directory:

Overall summary:
  Final result:                  Failed: see details below
  Exit code (Decimal):           -2068578304
  Exit facility code:            1204
  Exit error code:               0
  Exit message:                  The collation Latin1_General_CI-AS was not found.
  Start time:                    2013-02-19 13:59:31
  End time:                      2013-02-19 14:02:02
  Requested action:              RebuildDatabase

Is the collation Latin1_General_CI-AS something I have to enable or install?

I have tried the above with both "Latin1_General_CI-AS" and "Latin1_General_CP1_CI-AS" with the same results. 

Ideas?