OJDBC jdbc Jar File Introduction

-Ojdbc6.jar
Classes with JDK 1.6. It contains the JDBC driver classes
Except classes for NLS support in Oracle Object and Collection
Types.

-Ojdbc6_g.jar
Same as Ojdbc6.jar except compiled with "Javac-g" and contains
Tracing code.

-Ojdbc6dms.jar
Same as Ojdbc6.jar, except that it contains instrumentation to
Support DMS and limited java.util.logging calls.

-Ojdbc6dms_g.jar
Same as Ojdbc6_g.jar except that it contains instrumentation to
Support DMS.

note:the DMS versions of the jar files are the same as  
Standard jar files, except this they contain additional code
to the support Oracle Dynamic monitoring Service. They contain a
limited amount of tracing code. These can used
when Dms.jar are in the classpath. Dms.jar are provided as part of
Oracle application Server re Leases. As a result the DMS versions
of the jar files can only be used in an Oracle application Server
Environment.