Can't step into JDK source

Hello,
I'm using jswat 2.19, JDK 1.4.2, build 1.4.2-b28 on Window XP Pro.  I
create my session, add all relevant jars to the class path, set my
source path to my current project, and to the JDK source.  I set my
break point on a JDK class, and attempt to step in, but just step
over.  I've inadvertantly been able to step into the JDK source, so I
know it's possible.  I'm trying to step into
java.io.BufferedReader.ready().

I just went and re-ran JSwat, open BufferedReader.java, and tried to
set breakpoints, and get an error dialog, "There is no line number
information for this class".  Can I assume that only part of the JDK
is compiled with symbolic information, line numbers?
-- 
Thanks,
Jeff

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| Jeffery B. Rancier
| 
| Softechnics
| a METTLER TOLEDO company
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