Thaks for your email.
It seems that the name shoudn't have "-" or digit.
I exported the one that has problem and imported in another schema which has just simple name (TEST). It is OK now.

I am still surprize because I have this schema since 3 years ago and I haven't faced with problem before. I did so many export and import and because of so many test environemts always I distinguished them by for example schema+code (T1-AW23-7).
After applying the patch 8 to Oracle 9i I realized that when I import the sceham, the statistics don't update and the Last-Analyzed column in EM is empty. I checked the import log and saw the DBMS_Stat problem.
I can not find the reason why its worked before and it doesn't now.