vim syntax highliting doesn't work in muttng, works in mutt

In my .muttrc I have:

set editor="vim '+/^$'"

My .muttngrc just sources .muttrc :

miernik@szrenica:~$ cat .muttngrc | egrep -v "^#|^bind|^color|^macro" | uniq
source ~/.muttrc
source ~/.muttrc-color

set sidebar_visible="yes"
set sidebar_width=19

miernik@szrenica:~$

When vim is started from mutt to edit an e-mail, I get syntax
highliting. When it is done from muttng it doesn't. 

Why?

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Why software shouldn't be covered by patents
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