Mail Enabled Security Groups

Hi,

Should you be able to expand a mail enabled security groups in outlook 2010/exchange 2010 by pressing the '+' symbol next to the group? These are global groups do they need to be converted to universal? 

While trying to expand these I get the following..

"

Cannot perform the requested operation. The command selected is not valid for this recipient. There was an error while expanding the list. The list was not fully expanded.

"

Is this by design ?

Thanks