This is a known bug and is documented in MOS document ID 784038.1
If you are not particular about using exp/imp, try expdp and impdp which would be faster as well. Else you might have to apply the patch mentioned to fix this.
I like to copy the data from 10.2.0.4 oracle database to 184.108.40.206 db, so i tried to fired the traditional export from 11gr2 db server throw network
Apart that you should use expdp, you can't export a database using an exp utility from an higher version, you have to export using 10g exp utility, and import using 11g imp utility.
Export done in US7ASCII character set and AL16UTF16 NCHAR character set
server uses AL32UTF8 character set (possible charset conversion)
Couldn't this be a problem ? You should set NLS_LANG environment variable before exporting and importing.
I agree with Paul that if you are going to use exp you must use the 10.2 version to perform the export which the 11.2 imp can then process. If you use expdp to run the export then you should be able to use the 11.2 version providing you specify the version= parameter to identify that an older database is being read.
HTH -- Mark D Powell --