Repeated Error in accept: Bad file descriptor

[Time Less]

Just thought I'd try out PBXT. I created a database instance with 10
databases, inside each 100 tables. They were MyISAM tables. Then I did an
"alter table <name> engine=pbxt" across all of them. That worked fine. Then
I restarted MySQL, and now it won't come up. Error logs are filled with
thousands of:

# tail /var/log/mysql.err
100713 12:33:33 [ERROR] Error in accept: Bad file descriptor
100713 12:33:33 [ERROR] Error in accept: Bad file descriptor
100713 12:33:33 [ERROR] Error in accept: Bad file descriptor

To the tune of tens (or hundreds?) per second. I've tried restarting mysqld
with *ulimit -n 32768* and with my.cnf setting *open_files_limit = 32768* to
no effect. Does anyone have experience with this? Extensive Google searches
turn up nothing except esoteric OpenBSD problems or such.

MariaDB is MariaDB-server-5.1.44-75.el5.

-- 
timeless(ness)