Running Dovecot-1.1.5, I see this assertion failure: Panic: pop3-login: file sasl-server.c: line 75
(authenticate_callback): assertion failed: (client->auth_request ==
request) Error: pop3-login: Raw backtrace: 2 pop3-login 0x000000010000ac41
default_fatal_finish + 41 -> 3 pop3-login 0x000000010000acac
i_syslog_fatal_handler + 0 -> 4 pop3-login 0x000000010000a446 i_info +
0 -> 5 pop3-login 0x00000001000053a2
authenticate_callback + 126 -> 6 pop3-login 0x000000010000841c
auth_client_input_fail + 280 -> 7 pop3-login 0x0000000100007910
auth_client_input + 358 -> 8 pop3-login 0x000000010000e074
io_loop_handler_run + 272 -> 9 pop3-login 0x000000010000d449
io_loop_run + 38 -> 10 pop3-login 0x0000000100004864 main + 1572
-> 11 pop3-login 0x00000001000012fc start + 52 Error: child 1302 (login) killed with signal 6

This happens when I feed multiple user/pass lines to Dovecot all at
once like this: $ telnet gromit 110 Connected. Escape character is '^]'. +OK Dovecot ready. user x pass y user x pass y +OK +OK Connection closed by foreign host.

The four user/pass lines I pasted in all at once.

IMAP login does not crash when presented with multiple login commands,
but it does not read them all at once and needs prodding (in the form
of extra command lines sent later on) to read them. Actually it
appears to read the first two lines then stops reading until more data
comes in:

$ telnet gromit 143 Connected. Escape character is '^]'.

• OK Dovecot ready. a login a b b login c d c login e f d login g h e login i j a NO Authentication failed. b NO Authentication failed.

c NO Authentication failed.

d NO Authentication failed.

e NO Authentication failed.

• BAD Error in IMAP command received by server.
• BAD Error in IMAP command received by server.
• BAD Error in IMAP command received by server.
• BAD Error in IMAP command received by server. ^] telnet> q Connection closed.

You probably don't care about the odd imap-login behavior, but I tried
it and mentioned it just for completeness after seeing pop3-login crash.