Server spams "[INFO] Sending!" many times per second

Has anybody encountered this before? I thought I'd best ask before starting the process of fiddling with all the plugins and bukkit builds and things.

It doesn't seem to happen on vanilla minecraft.
Also there are occasional 5-10 minute breaks between bouts of Sending!ness.

Running CB#556 on ubuntu 9.10 64 bit, java 1.6.0_15
Plugins (Up to date):
Borderguard Lite (Circular)
BoundaryKill
CraftBook
Essentials
HeroicDeath
iChat
LWC
McMMO
Permissions
SkyPirates
WorldEdit

 

well the first thing most everyone is going to tell u is to update your java to the latest version.

Then they are going to say to take out ur plugins and see if it happens, then add your plugins in one at a time until u find the one that may be doing this. But you already know that cause you said u didn't want to do that. Only trouble is that is probably the only way to find out what is doing it.