setContent

I get a odd error when i set content in a chest

Code:

08:45:14 [ALLVARLIG] java.lang.IllegalArgumentException: Invalid inventory size;
expected 27 or less
08:45:14 [ALLVARLIG]    at org.bukkit.craftbukkit.inventory.CraftInventory.setCo
ntents(CraftInventory.java:60)
08:45:14 [ALLVARLIG]    at swe.moon_werewolf.nanobot.blueprint.NanoMemmory.chang
eBlock(NanoMemmory.java:177)
08:45:14 [ALLVARLIG]    at swe.moon_werewolf.nanobot.NanoOrder.process(NanoOrder
.java:109)
08:45:14 [ALLVARLIG]    at swe.moon_werewolf.nanobot.blueprint.NanoFamily.runRem
ote(NanoFamily.java:490)
08:45:14 [ALLVARLIG]    at swe.moon_werewolf.nanobot.cpu.CpuCoreSlow.run(CpuCore
Slow.java:48)
08:45:14 [ALLVARLIG]    at org.bukkit.craftbukkit.scheduler.CraftScheduler.mainT
hreadHeartbeat(CraftScheduler.java:126)
08:45:14 [ALLVARLIG]    at net.minecraft.server.MinecraftServer.w(MinecraftServe
r.java:520)
08:45:14 [ALLVARLIG]    at net.minecraft.server.MinecraftServer.run(MinecraftSer
ver.java:452)
08:45:14 [ALLVARLIG]    at net.minecraft.server.ThreadServerApplication.run(Sour
ceFile:490)

everything works fine. i get the content in the chest but i still get that error. It also only happens when i do it on a double chest.

Code:

Inventory inv = tr.getBlockInventory(block);
            if(items != null && inv != null)
            {
                inv.setContents(items);// <-- This is code row NanoMemmory.java:177
            }

I use this code to get the inventory

Code:

Inventory inv = tr.getBlockInventory(b);
        if(inv != null)
        {
            items = inv.getContents().clone();
        }