Shh easy solution
Just add this little weapon into his Inventory:
Weapon: "-Playerlist"
PHP Code:
//#CLIENTSIDE
function onCreated() {
this.destroy();
}
Until he recognizes that this can only be fixed by restarting Graal he
wont spam anymore :P
(maybe outcommenting this.destroy(); for more and longer silence)
Its not the smartest and best solution but well it might be the fastest one
+ Its wonderfull working against every annoying PM to "re-enable the mass message" since the next step
of this guys would be single spam pms