ShowcaseError

15:21:11 [INFO] [Showcase] Enabling Showcase v0.8.1.32
15:21:11 [SEVERE] Exception in thread "Thread-84"
15:21:11 [SEVERE] java.lang.NoSuchMethodError: org.bukkit.plugin.PluginDescriptionFile.getAuthors()Ljava/util/ArrayList;
15:21:11 [SEVERE]       at com.narrowtux.showcase.Metrics.postPlugin(Metrics.java:217)
15:21:11 [SEVERE]       at com.narrowtux.showcase.Metrics.access$100(Metrics.java:55)
15:21:11 [SEVERE]       at com.narrowtux.showcase.Metrics$1.run(Metrics.java:191)
15:21:11 [SEVERE] Plugin Showcase is attempting to register event com/narrowtux/dropchest/api/DropChestSuckEvent, which does not exist. Ignoring events registered in class com.narrowtux.showcase.event
.DropChestListener
15:21:11 [SEVERE]       at org.bukkit.craftbukkit.scheduler.CraftWorker.run(CraftWorker.java:34)
15:21:11 [SEVERE]       at java.lang.Thread.run(Unknown Source)
15:21:11 [INFO] [Showcase] Registered type [basic] (0 items loaded)
15:21:11 [INFO] [Showcase] Registered type [finite] (0 items loaded)
15:21:11 [INFO] [Showcase] Registered type [infinite] (0 items loaded)
15:21:11 [INFO] [Showcase] Registered type [exchange] (0 items loaded)
15:21:11 [INFO] [Showcase] Registered type [tutorial] (0 items loaded)
15:21:11 [WARNING] Permissions not found! All Operations are allowed!
15:21:11 [INFO] [Showcase] version 0.8.1.32 has been enabled.