Bug #18020 IM connect problem

Description:
Release build of 5.0.19.

Test failure:

im_utils                       [ fail ]

Errors are (from PATH/mysqltest-time) :
mysqltest: In included file "./include/im_check_os.inc": At line 1: Could not open connection 'dflt_server_con': 2002 Can't
 connect to local MySQL server through socket 'PATH/mysqld_1.sock' (2)
(the last lines may be the most important ones)

Ending Tests

===---===---===---===---===---===--- OCCURRED:
cane-5.0-pro.log   normal
cane-5.0-standard.log   normal
hpita2-64bit-5.0-max.log   normal
hpita2-64bit-5.0-standard.log   normal
pegasos3-glibc23-5.0-debug.log   normal
pegasos3-glibc23-5.0-standard.log   normal
sol9x86-5.0-pro-gpl.log   normal
sol9x86-5.0-standard.log   normal

Same error (on varying subsets of these platforms, but always including "cane") in the tests
im_daemon_life_cycle
im_life_cycle
im_options_set
im_options_unset

How to repeat:
Detected by running the test suite.

This is a duplicate of BUG#19391.

I have to re-open this bug:
In the release build of 5.0.24, it still occurs.
(It has also been seen on 20, 21, 22, and 23)

The sources for 5.0.24 include the two patches for bug#19391, which were claimed to fix this issue (double-checked using "bk changes").

This is the full list for current 5.0.24:

=====
im_daemon_life_cycle           [ fail ]

Errors are (from /PATH/mysqltest-time) :
mysqltest: In included file "./include/im_check_os.inc": At line 1: Could not open connection 'dflt_server_con': 2002 Can't
 connect to local MySQL server through socket '/PATH/mysqld_1.sock' (2)
(the last lines may be the most important ones)
=====

Same symptom for tests "im_life_cycle", "im_options_set", "im_options_unset", "im_options_unset", and "im_utils".

Occurs for all these tests in the RPM builds on "melody" and "sles9-x86":
Do-rpm-melody-5.0-pro-gpl.sles9.log   normal
Do-rpm-melody-5.0-pro.sles9.log   normal
Do-rpm-melody-5.0-standard.sles9.log   normal
Do-rpm-sles9-x86-5.0-pro-gpl.sles9.log   normal
Do-rpm-sles9-x86-5.0-pro.sles9.log   normal
Do-rpm-sles9-x86-5.0-standard.sles9.log   normal

Some of these failures occur also here:
Do-rpm-rhas3-x86-5.0-pro.rhel3.log   normal
sol9x86-5.0-max.log   normal
sol9x86-5.0-max.log   NDB
sol9x86-5.0-pro.log   normal
sol9x86-5.0-standard.log   normal

A patch for this bug:
http://lists.mysql.com/commits/10998

See BUG#21331 for more info.

Merged into 5.0 tree, currently tagged 5.0.25;
merged into 5.1 tree, currently tagged 5.1.12-beta.

Test suite change. No changelog entry needed.