Text conversion of the file '.pdf' failed

Hi,
Webcenter Content Version: 11gR1-11.1.1.7.0-idcprod1-130304T092605 (Build:7.3.4.184) is installed in my machine.

I have enabled OracleTextSearch. When I check-in a text file the conversion works and the indexer process completes fine. But there is a problem with PDF file.

Below is the System Audit log for the indexer when a pdf file is checked-in:

>indexermonitor/6	12.26 12:24:50.071	SubjectManager	Attempting to start automated work.
>indexermonitor/6	12.26 12:24:50.071	SubjectManager	touching lock file /ucm/domains/ucm_domain/ucm/cs/search/lock/update_lock.dat
>indexermonitor/6	12.26 12:24:50.072	index update work	Starting indexing update (action=0).
>indexermonitor/7	12.26 12:24:50.074	index update notify	touching lock file /ucm/domains/ucm_domain/ucm/cs/search/lock/update_lock.dat
>indexer/6	12.26 12:24:50.075	index update work	Retrieving indexer workspace: Provider name is 'SystemDatabase'
>indexer/7	12.26 12:24:50.076	index update work	/ucm/domains/ucm_domain/ucm/cs/search/search.cfg doesn't exist.
>indexer/6	12.26 12:24:50.076	index update work	Retrieving indexer workspace: Provider name is 'SystemDatabase'
>indexer/7	12.26 12:24:50.077	index update work	isRebuild?false; IndexerStep:Init;  Class:intradoc.indexer.Indexer
>indexer/7	12.26 12:24:50.077	index update work	isRebuild?false; IndexerStep:CheckCollection;  Class:intradoc.indexer.IndexerCollectionManager
>indexer/7	12.26 12:24:50.078	index update work	isRebuild?false; IndexerStep:BuildChanges;  Class:entoracle.indexer.EOIndexerBuildChanges
>indexer/7	12.26 12:24:50.103	index update work	Saving 1 update changes
>indexer/7	12.26 12:24:50.103	index update work	isRebuild?false; IndexerStep:PreIndexingStep;  Action:preIndexingStep
>indexer/7	12.26 12:24:50.103	index update work	isRebuild?false; IndexerStep:CheckForWork;  Class:intradoc.indexer.Indexer
>indexer/7	12.26 12:24:50.104	index update work	Found work:Additions; Type:+; Change count: 1
>indexer/7	12.26 12:24:50.104	index update work	isRebuild?false; IndexerStep:IndexAdditions;  Class:intradoc.indexer.CommonIndexerBulkLoader
>indexer/7	12.26 12:24:50.104	index update work	IndexerBulkLoader doing 'IndexAdditions'