BLS transaction SocketTimeoutException

I have a transaction which has a number of reads/writes to 2 Oracle databases. It has been running OK for a number of months but now it has stopped writing to one of the Oracle databases. When I execute the transaction within the Logic Editor I get the message: Error executing transaction: java.net.SocketTimeoutException: Read timed out. By playing around with the transaction it appears that executing the SQL Query on this Oracle database is what is causing the timeout. However, running the query in the Query Template test mode works fine! Also, other applications running on this database are running OK. What could be causing this problem?

Thanks,

John.