There are multiple solutions to solve this issue
1. Shutdown the Concurrent Processing server.
2. Manually delete all the temporary files under the $INST_TOP/logs/ora/10.1.2/reports/cache path
3. Startup up the Concurrent Processing server.
Other Solution is that
As a current workaround to patch 9032800:
Change the Oracle Reports configuration file $INST_TOP/ora/10.1.2/reports/conf/rwbuilder.conf and bouncing the services.
property name="cacheSize" value="50" to
property name="cacheSize" value="0"
This change will be lost when Autoconfig is run. Apply patch 8602992 for permanent solution