[Dovecot] Panic in 2.0.9 imap-client

[Mike Abbott]

> Jan 17 12:06:20 server dovecot: imap(XXXX at YYYYYYY): Panic: file imap-client.c: line 570 (client_continue_pending_input): assertion failed: (!client->handling_input)

I just saw this with 2.0.8 too.  Backtrace is:

0   __kill + 10
1    abort + 177
2    0x10d928000 + 143594
3    0x10d928000 + 139194
4    i_panic + 159
5    client_continue_pending_input + 196
6    cmd_idle + 188
7    client_command_input + 36
8    client_command_input + 416
9    client_handle_input + 134
10   client_input + 118
11   io_loop_call_io + 70
12   io_loop_handler_run + 227
13   io_loop_run + 72
14   master_service_run + 27
15   main + 703
16   start + 52