To debug lock timeout errors, set derby.locks.monitor=true and derby.locks.deadlockTrace=true in derby.properties. This will print the lock table information to the derby.log when the timeout happens. If you also set derby.language.logStatementText=true, then all the statements executed on the system will be written out to the derby.log
The log file containing the information referenced will usually be the one named with the hostname on which Tomcat is running. On a simple server (e.g. development environment) this is localhost.<datestamp>.log
With Subversion 1.5 or later the merge is recorded on your local working copy in the svn:mergeinfo property. So this information is not lost.
You can see the merged revisions if you use svn log -g