Oracle 11g Release 2(220.127.116.11.0) client for x86-64 has a new bug(9496209). I was able to reproduce the issue after about 2-3 days of repeated execution.
With a Java module that uses the thick client(OCI) to connect through JDBC and initializes a C3P0 connection pool, the module would intermittently crash. Here’s an example of how to reproduce the problem. Of course, you would need C3P0 libraries in your environment.