When doing a server side message body search I got this in the logs:
Apr 14 22:32:24 imap(support@junkemailfilter.com): Panic: file message-parser.c: line 698 (preparsed_parse_prologue_more): assertion failed: (ctx->part->children != NULL) Apr 14 22:32:24 imap(support@junkemailfilter.com): Error: Raw backtrace: /usr/lib/dovecot/libdovecot.so.0(+0x5f45a) [0x7f6eab1d745a] -> /usr/lib/dovecot/libdovecot.so.0(+0x5f4a6) [0x7f6eab1d74a6] -> /usr/lib/dovecot/libdovecot.so.0(i_error+0) [0x7f6eab197d4f] -> /usr/lib/dovecot/libdovecot.so.0(+0x52863) [0x7f6eab1ca863] -> /usr/lib/dovecot/libdovecot.so.0(message_parser_parse_next_block+0x29) [0x7f6eab1ca349] -> /usr/lib/dovecot/libdovecot.so.0(message_search_msg+0x5d) [0x7f6eab1cc51d] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0x9d558) [0x7f6eab4d5558] -> /usr/lib/dovecot/libdovecot-storage.so.0(mail_search_args_foreach+0x3c) [0x7f6eab4acc3c] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0x9d289) [0x7f6eab4d5289] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0x9e2fd) [0x7f6eab4d62fd] -> /usr/lib/dovecot/libdovecot-storage.so.0(index_storage_search_next_nonblock+0xe8) [0x7f6eab4d6938] -> /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_search_next_nonblock+0x27) [0x7f6eab4b1057] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x41a78f] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x41abf9] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x40ff75] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x414f5d] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x4140c0] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x4141ad] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x41442d] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x41479f] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_call_io+0x36) [0x7f6eab1e63a6] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run+0xa7) [0x7f6eab1e7407] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_run+0x28) [0x7f6eab1e6348] -> /usr/lib/dovecot/libdovecot.so.0(master_service_run+0x13) [0x7f6eab19ca03] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x41d997] -> /lib64/libc.so.6(__libc_start_main+0xfd) [0x7f6eaadfecdd] -> dovecot/imap support@junkemailfilter.com 127.0.0.1 UID SEARCH [0x40a4d9] Apr 14 22:32:24 imap(support@junkemailfilter.com): Fatal: master: service(imap): child 28156 killed with signal 6 (core dumps disabled)