Cannot open Office documents in SharePoint 2010 when accessing sharEPoint through a Checkpoint VPN

Hello,

When accessing SharePoint through a checkpoint VPN the URL for the SharePoint site changes and looks like this.

https://remote.xxxxxx.com/PT/http://sharepoint/default.aspx

all functionality works but when opening any office type document I get this error

The checkpoint device is adding an extra URL to so im guessing it doesn't know where to find the document.

Does anyone know how to resolve this?