Cannot serialize session attribute

[Ramon Misho]

Hello iBatis people:

I am using Eclipse Version: 3.0.0 and Tomcat 5.0.19.

I edit a java file (in the Eclipse), and click on the 'Save' button. The 
'Reloading" starts as expected.   However, very often (but not all the time), I 
get the following error messages although they have no impact on the compiling 
process.  

                -----here are some parts of the error message-----------
                Cannot serialize session attribute myfileBean for session 
A2F0ED8D3C199E076B84EB3CF792C6FD
        .....................
        .....................
                IOException while loading persisted sessions: 
java.io.WriteAbortedException: writing aborted; 
java.io.NotSerializableException: 
com.ibatis.sqlmap.engine.mapping.statement.PaginatedDataList
                java.io.WriteAbortedException: writing aborted; 
java.io.NotSerializableException:com.ibatis.sqlmap.engine.mapping.statement.PaginatedDataList
        .....................
                ..................etc
                
                
The 'myfileBean' is the name of one of my JAVA files.   The strange thing is 
that when this error is generated, I am usually working with another JAVA file.

Any ideas?

Thanks.
Ramon