Here are my conclusions. You can use QuickOffice offline to edit a document but the file you'll be working with must be locally saved on your device (PC, laptop, tablet, mobile, etc.) and won't be updated on the server automatically because you are disconnected, you will have to update the file once you restablish your Internet connection.
After reading this: http://support.quickoffice.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=494
Here are my conclusions. You can use QuickOffice offline to edit a document but the file you'll be working with must be locally saved on your device (PC, laptop, tablet, mobile, etc.) and won't be updated on the server automatically because you are disconnected, you will have to update the file once you restablish your Internet connection.