You'll find that Gmail provides robust, business-class features, many of which are not available in GroupWise.. However, some of the features and capabilities you might be used to in GroupWise are not available in Google Apps or were not included in our implementation, including:
Message flags (such as Important and Follow-up) -- However, you can use stars and labels to highlight messages in your inbox.
Message sorting -- You can't click the column headings in your Inbox to sort messages.
Drag-and-drop for attachments -- To attach a file to an email message, you must use a dialog box to choose it from your desktop. You can activate the Drag and Drop Lab to enable the functionality.
Message recall -- If you send a message that you wish you hadn't, you can't recall it to prevent recipients from opening it. The option is available in Labs and the setting to change the the number of seconds for delay is on the Settings>General tab.
Read/Return receipts -- There's no option to get a notification when a recipient opens your message.
View options -- You can't change the placement of the reading pane or move any components in the Mail window.