db2 9.5 alter table alter column报911错误

[db2inst1:/citic/db2inst1]$ db2 "alter table 表名 alter column 字段名 set data type CHARACTER(42) "
DB21034E  The command was processed as an SQL statement because it was not a
valid Command Line Processor command.  During SQL processing it returned:
SQL0911N  The current transaction has been rolled back because of a deadlock
or timeout.  Reason code "68".  SQLSTATE=40001

数据库版本：
Database server        = DB2/HPUX-IA64 9.5.3

原字段类型   
CHARACTER(40) DEFAULT '',

自己单独做过测试，别的表字段是可以成功的，说明语法没问题，但这个表的字段却不行，表中有几百行数据，求大神指导。收起