Please help, Gal Listener not working

I've been trying to use galistener as my voting plugin but it keeps throwing back an exception anytime someone votes
"[14:41:48] [Craft Scheduler Thread - 156/WARN]: Exception in thread "Craft Scheduler Thread - 156"

[14:41:48] [Craft Scheduler Thread - 156/WARN]: org.apache.commons.lang.UnhandledException: Plugin GAListener v1.3.2 generated an exception while executing task 490
at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:56)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NoSuchMethodError: org.bukkit.Server._INVALID_getOnlinePlayers()[Lorg/bukkit/entity/Player;
at com.swifteh.GAL.RewardTask.run(RewardTask.java:37)
at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftTask.run(CraftTask.java:71)
at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:53)
... 3 more"

Does anyone know what might be going on? it's a 1.8.8 server running version 1.3.2 galistener.

 

@Shadowzombie115
This is a known problem: GAListener uses the old version of OnlinePlayers. There is currently no fix for this plugin. You should look around and find a replacement for it.