diff --git a/SPD-classes/src/main/java/com/watabou/utils/Random.java b/SPD-classes/src/main/java/com/watabou/utils/Random.java
index 7fe0a3891..73112d553 100644
--- a/SPD-classes/src/main/java/com/watabou/utils/Random.java
+++ b/SPD-classes/src/main/java/com/watabou/utils/Random.java
@@ -121,6 +121,10 @@ public class Random {
 			sum += probs[i];
 		}
 		
+		if (sum <= 0) {
+			return null;
+		}
+		
 		float value = Float( sum );
 		
 		sum = probs[0];