ORA-12705 invalid or unknown NLS parameter value specified Cause: There are two possible causes: Either an attempt was made to issue an ALTER SESSION statement with an invalid NLS parameter or value; or the NLS_LANG environment variable contains an invalid language, territory, or character set. Action: Check the syntax of the ALTER SESSION command and the NLS parameter, correct the syntax and retry the statement, or specify correct values in the NLS_LANG environment variable. For more information about the syntax of the ALTER SESSION command, see Oracle8i SQL Reference.
Cause: There are two possible causes: Either an attempt was made to issue an ALTER SESSION statement with an invalid NLS parameter or value; or the NLS_LANG environment variable contains an invalid language, territory, or character set.
Action: Check the syntax of the ALTER SESSION command and the NLS parameter, correct the syntax and retry the statement, or specify correct values in the NLS_LANG environment variable. For more information about the syntax of the ALTER SESSION command, see Oracle8i SQL Reference.
ORA-12705 指定了无效的或未知的NLS参数值。
原因：有两种可能的原因：发出的alter session命令使用了一个无效的NLS参数;或者NLS_LANG环境变量包含一个无效的语言，地域，或者字符集.
解决方法：
检查一个alter session的语法和所用的nls参数,较正后重试一次，或使用NLS_LANG环境变量指定一个正确的值，有关alter session命令语法更多的信息可以看一下"Oracle8i SQL Reference"这个联机文档。总结起来，我认为还是你的客户机的NLS_LANG设得不正确。
AMERICAN_AMERICA.WE8ISO8859P1,即可。