Logstash hangs after some time

Logstash 1.4.2 hangs after some time. This used to work perfectly earlier but last few weeks been giving issues. Appreciate quick help.

"LogStash::Runner" prio=10 tid=0x00007f7b4c009000 nid=0x5daa in Object.wait() [0x00007f7b52e41000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.Thread.join(Thread.java:1288)
- locked <0x00000000e2323d58> (a java.lang.Thread)
at org.jruby.internal.runtime.NativeThread.join(NativeThread.java:75)
at org.jruby.RubyThread.join(RubyThread.java:696)
at org.jruby.RubyThread$INVOKER$i$0$1$join.call(RubyThread$INVOKER$i$0$1$join.gen)
at org.jruby.internal.runtime.methods.JavaMethod$JavaMethodN.call(JavaMethod.java:661)
at org.jruby.internal.runtime.methods.DynamicMethod.call(DynamicMethod.java:198)
at org.jruby.runtime.callsite.CachingCallSite.cacheAndCall(CachingCallSite.java:306)
at org.jruby.runtime.callsite.CachingCallSite.call(CachingCallSite.java:136)
at org.jruby.ast.CallNoArgNode.interpret(CallNoArgNode.java:60)
at org.jruby.ast.NewlineNode.interpret(NewlineNode.java:105)
at org.jruby.ast.BlockNode.interpret(BlockNode.java:71)
at org.jruby.evaluator.ASTInterpreter.INTERPRET_METHOD(ASTInterpreter.java:74)
at org.jruby.internal.runtime.methods.InterpretedMethod.call(InterpretedMethod.java:139)
at org.jruby.internal.runtime.methods.DefaultMethod.call(DefaultMethod.java:182)
at org.jruby.runtime.callsite.CachingCallSite.cacheAndCall(CachingCallSite.java:306)
at org.jruby.runtime.callsite.CachingCallSite.call(CachingCallSite.java:136)
at opt.logstash.lib.logstash.runner.block_3$RUBY$main(/opt/logstash/lib/logstash/runner.rb:98)
at opt$logstash$lib$logstash$runner$block_3$RUBY$main.call(opt$logstash$lib$logstash$runner$block_3$RUBY$main)
at org.jruby.runtime.CompiledBlock19.yield(CompiledBlock19.java:135)
at org.jruby.runtime.Block.yield(Block.java:142)
at org.jruby.RubyArray.eachCommon(RubyArray.java:1606)
at org.jruby.RubyArray.each(RubyArray.java:1613)
at org.jruby.RubyArray$INVOKER$i$0$0$each.call(RubyArray$INVOKER$i$0$0$each.gen)
at org.jruby.runtime.callsite.CachingCallSite.cacheAndCall(CachingCallSite.java:316)
at org.jruby.runtime.callsite.CachingCallSite.callBlock(CachingCallSite.java:145)
at org.jruby.runtime.callsite.CachingCallSite.callIter(CachingCallSite.java:154)
at opt.logstash.lib.logstash.runner.method__7$RUBY$main(/opt/logstash/lib/logstash/runner.rb:96)
at opt$logstash$lib$logstash$runner$method__7$RUBY$main.call(opt$logstash$lib$logstash$runner$method__7$RUBY$main)
at opt$logstash$lib$logstash$runner$method__7$RUBY$main.call(opt$logstash$lib$logstash$runner$method__7$RUBY$main)
at org.jruby.runtime.callsite.CachingCallSite.cacheAndCall(CachingCallSite.java:326)
at org.jruby.runtime.callsite.CachingCallSite.call(CachingCallSite.java:170)
at opt.logstash.lib.logstash.runner.file(/opt/logstash/lib/logstash/runner.rb:215)
at opt.logstash.lib.logstash.runner.load(/opt/logstash/lib/logstash/runner.rb)
at org.jruby.Ruby.runScript(Ruby.java:811)
at org.jruby.Ruby.runScript(Ruby.java:804)
at org.jruby.Ruby.runNormally(Ruby.java:673)
at org.jruby.Ruby.runFromMain(Ruby.java:522)
at org.jruby.Main.doRunFromMain(Main.java:395)
at org.jruby.Main.internalRun(Main.java:290)
at org.jruby.Main.run(Main.java:217)
at org.jruby.Main.main(Main.java:197)