bug in trees-ostream.c ?

It appears to be that in this commit: 2d77a432 the code should have been:

if (chunk_size >= (SSIZE_MAX - crypto_box_SEALBYTES))

The difference being >= rather than <.

Also, it should probably be noted that this plugin doesn't work when your mail format in dovecot is set to maildir. I was getting strange errors when trying to read folders. Once I switched it to mdbox, everything worked great!