You can use the Proxy, MultiLogin or Login method in the Application object. These methods will access the account object when that account is not active in the GroupWise window. Login and MultiLogin method requires a user ID and password of the account. The MultiLogin method requires only a UserID with a Trusted Application (GroupWise 5.5 and later versions). Assuming the account has the proxy rights then you can use the Proxy() method to access the account object.
set oAccount = GroupWise.account.parent.proxy("test") msgbox oAccount.owner.displayname
Hope this helps.