[dev] imp patch

[Marko Djukic]

problem:
- often i click through an inbox and open multiple emails in tabs to read them
quicker.
- however in the meantime filters might kick in on the inbox and flush out
emails from the inbox
- clicking then to reply/forward/redirect emails that have been opened in
separate tabs creates object not found errors

this patch traps for a message index not returning a message body and tries to
exit gracefully defaulting the user to a new composition.

only thing is i couldn't figure out how to exit gracefully on line 934 with a
FWD_DIGEST...

marko