Bukkit

I get the following when reloading:

[18:40:46] [Server thread/ERROR]: Could not load 'plugins/SkyText-1.15.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.NoClassDefFoundError: com/sk89q/worldedit/FilenameException
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:328) ~[minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.craftbukkit.v1_7_R4.CraftServer.loadPlugins(CraftServer.java:364) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.craftbukkit.v1_7_R4.CraftServer.reload(CraftServer.java:837) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.Bukkit.reload(Bukkit.java:303) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:23) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:180) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.craftbukkit.v1_7_R4.CraftServer.dispatchCommand(CraftServer.java:740) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.PlayerConnection.handleCommand(PlayerConnection.java:957) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.PlayerConnection.a(PlayerConnection.java:818) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.PacketPlayInChat.a(PacketPlayInChat.java:28) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.PacketPlayInChat.handle(PacketPlayInChat.java:47) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.NetworkManager.a(NetworkManager.java:157) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.ServerConnection.c(SourceFile:134) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.MinecraftServer.v(MinecraftServer.java:667) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.DedicatedServer.v(DedicatedServer.java:258) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.MinecraftServer.u(MinecraftServer.java:558) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java:469) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:628) [minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
Caused by: java.lang.NoClassDefFoundError: com/sk89q/worldedit/FilenameException
at java.lang.Class.forName0(Native Method) ~[?:1.7.0_65]
at java.lang.Class.forName(Class.java:270) ~[?:1.7.0_65]
at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:40) ~[minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:127) ~[minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
... 19 more
Caused by: java.lang.ClassNotFoundException: com.sk89q.worldedit.FilenameException
at java.net.URLClassLoader$1.run(URLClassLoader.java:366) ~[?:1.7.0_65]
at java.net.URLClassLoader$1.run(URLClassLoader.java:355) ~[?:1.7.0_65]
at java.security.AccessController.doPrivileged(Native Method) ~[?:1.7.0_65]
at java.net.URLClassLoader.findClass(URLClassLoader.java:354) ~[?:1.7.0_65]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:77) ~[minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:62) ~[minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_65]
at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_65]
at java.lang.Class.forName0(Native Method) ~[?:1.7.0_65]
at java.lang.Class.forName(Class.java:270) ~[?:1.7.0_65]
at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:40) ~[minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:127) ~[minecraft_server.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
... 19 more