Thanks Friend, I use l2jfrozen, the code is different, as I do?
// If in Arena, do nothing
if (isInsideZone(ZONE_PVP) || targetPlayer.isInsideZone(ZONE_PVP))
return;
And when I add your code generates this error
[javac] if (isInsideZone(ZONE_PVP) || targetPlayer.isInsideZone(ZONE_PVP) && (!isInSiege() && !targetPlayer.isInSiege()))
[javac] ^
[javac] symbol: method isInSiege()
[javac] location: variable targetPlayer of type L2PcInstance
[javac] 2 errors
[javac] 1 warning