Not quite.

Have a look at BOL


mk:@MSITStore:C:\Program%20Files\Microsoft%20SQL%20Server\80\Tools\Books\coprompt.chm::/cp_dtsrun_95kp.htm


/A global_variable_name:typeid=value

Specifies a package global variable, where typeid = type identifier for
the data type of the global variable. The entire argument string can be
quoted. This argument can be repeated to specify multiple global
variables. See the Remarks section for the different available type
identifiers available with global variables.

To set global variables with this command switch, you must have either
Owner permission for the package or the package must have been saved
without DTS password protection enabled. If you do not have Owner
permission, you can specify global variables, but the values used will
be those set in the package, not those specified with the /A command
switch.


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