MalFormedURLException from Oracle query

I have a Java program that access an Oracle
database using the Oracle ThinClient. If I access a
table of type VARCHAR2 that has values that look
like a Date ( 2002-09-03 12:23:34 ) or a table of
type Date, the return value generates a
MalFormedURLException. I get the same error when
using JCompiler/Console or AntFarm.

Compiling and running the same Java code file in
the DOS Command Prompt does not generate any
error.

I am using Java 1.4.0 in a Windows NT4.0
environment.

I can supply the source file if it would help.

Thanks,
Frank