Bug found by @ep0ch2 in #250

Many thanks for this, the following settings work:

• DISABLE_AMAVIS=0
• DISABLE_SPAMASSASSIN=1
• DISABLE_CLAMAV=1

however with disable_amavis=1 i can't send/receive emails. so perhaps some extra config changes are needed,

@KyleOndy: I'm opening this issue for reminder.
Will you be able to work on it? May I help?

Thank you.