When I drag a file to an application, the path given to it ends in a newline. For example, drag a file to a terminal screen, and it immediately tries to execute the file path as if I'd hit return. Worse, if I drag it to a dialog box that accepts paths, the text field will have an unprintable newline at the end. In meld (a merge program I use) this causes errors because it tries to open the path "/my/path/file\n"
This is the correct behavior. Passing URIs via DnD, they must be formatted in a special way (and terminated with newlines). Smart applications will remove the trailing newlines prior to inserting the path.