Java cmd was running for around 18hrs, woke this morning with the following warning message. Posting it here in case it is needed for development improvements.
2013-12-27 04:05:02.198:WARN:oejs.ServletHandler:qtp753866237-1087: Error for /nxt
java.lang.OutOfMemoryError: Java heap space
Im on win7 64bit firefox
EDIT
Re started Java cmd and seems to be running again but with this extra line which I have not seen before.
[2013-12-27 06:34:32.481] 11: java.util.ConcurrentModificationException