Hello all, I have troubles with backport some errors from 5.5 to 5.1 http://dev.mysql.com/doc/refman/5.1/en/server-system-variables.html#sysvar_q... http://dev.mysql.com/doc/refman/5.5/en/error-messages-server.html#error_er_q... Last error in mysql 5.1.49 - 1640. If i just add ER_QUERY_CACHE_DISABLED --- a/sql/share/errmsg.txt      2010-07-09 16:35:08.000000000 +0400 +++ b/sql/share/errmsg.txt      2010-07-31 20:41:47.244015659 +0400 @@ -6213,3 +6213,7 @@ ER_DEBUG_SYNC_HIT_LIMIT   eng "debug sync point hit limit reached"   ger "Debug Sync Point Hit Limit erreicht" + +ER_QUERY_CACHE_DISABLED +  eng "Query cache is disabled; restart the server with query_cache_type=1 to enable it" + then error code of ER_DEBUG_SYNC_HIT_LIMIT  is 1641 (instead of 1651 what i need). If i try: --- a/sql/share/errmsg.txt      2010-07-09 16:35:08.000000000 +0400 +++ b/sql/share/errmsg.txt      2010-07-31 20:41:47.244015659 +0400 @@ -6213,3 +6213,8 @@ ER_DEBUG_SYNC_HIT_LIMIT  eng "debug sync point hit limit reached"  ger "Debug Sync Point Hit Limit erreicht" + +start-error-number 1010 +ER_QUERY_CACHE_DISABLED +  eng "Query cache is disabled; restart the server with query_cache_type=1 to enable it" + then mysql doesn't start with error in bootstrap.log like: "mysqld can't srart because errmsg.sys has only 642 errors, when last error number is ...." How can i backport error from mysql 5.5 to mysql 5.1 right? Now i solve trouble like: --- a/sql/share/errmsg.txt      2010-07-09 16:35:08.000000000 +0400 +++ b/sql/share/errmsg.txt      2010-07-31 20:41:47.244015659 +0400 @@ -6213,3 +6213,27 @@ ER_DEBUG_SYNC_HIT_LIMIT   eng "debug sync point hit limit reached"   ger "Debug Sync Point Hit Limit erreicht" + +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_01 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_02 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_03 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_04 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_05 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_06 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_07 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_08 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_09 + eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED_WRITE_SPACE_10 +  eng "Fix error number for ER_QUERY_CACHE_DISABLED" +ER_QUERY_CACHE_DISABLED +  eng "Query cache is disabled; restart the server with query_cache_type=1 to enable it" + But this is ugly hack. What do you think about my trouble and ways for solve? Best regards, Oleg.