BalusC is right. See here: http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Throwable.html#printStackTrace()
In particular:
Note the presence of lines containing
the characters “…”. These lines
indicate that the remainder of the
stack trace for this exception matches
the indicated number of frames from
the bottom of the stack trace of the
exception that was caused by this
exception (the “enclosing” exception).
This shorthand can greatly reduce the
length of the output in the common
case where a wrapped exception is
thrown from same method as the
“causative exception” is caught.
What this means in your example is that:
BasicDataSource.java line 1136 caught the ClassNotFoundException thrown on line 1130 and reraised it as a SQLNestedException. Hence the remainder of the stacktrace for the ClassNotFoundException matches the SQLNestedException above and the stacktrace is printed in this more concise format.