Scenario

Operating System HP Unix
Oracle 8.1.6
Before we had different character set of American_America.AR8ISO8859P6 due to the client requirements we have changed the character in Unix Server in .profile and Props$ table to American_America.AR8MSWIN1256, is their any other file we need to change Character set. Please do advise.

Query-Problem

When I run exp command and want to export a db, there are some errors
infomations displayed is below:
. exporting synonyms
EXP-00008: ORACLE error 6553 encountered
ORA-06553: PLS-561: character set mismatch on value for parameter
'SHORTNAME'
EXP-00000: Export terminated unsuccessfully
Could you tell me why?
Thank you very much.

Your urgent solution in this regards is highly appreciated. Looking forward for your affirmative response i remain.