Comment 8 for bug 499797

a tiny patch is here: lp:~gtg-user/gtg/file-attach/
I've found a bug, that can be reproduced like this:
1) drag and drop a file. sometimes, the file:// url is not recognized on the fly (which is also a bug)
2) press enter and backspace. the file is recognized, but the internal fileurl is set to <filename><enter><backspace>
3) opening such a file is impossible.

This one is probably a GTG bug (that existed before your work, for web urls) but it's quite noticeable, so it should be fixed before merging. I'll look at it over the weekend if you don't have time to do it.