diff --git a/server/src/com/cloud/api/ApiDispatcher.java b/server/src/com/cloud/api/ApiDispatcher.java
index 2f3b366ad7e..b499afa0cad 100644
--- a/server/src/com/cloud/api/ApiDispatcher.java
+++ b/server/src/com/cloud/api/ApiDispatcher.java
@@ -98,10 +98,14 @@ public class ApiDispatcher {
             Throwable cause = ite.getCause();
             if (cause instanceof InvalidParameterValueException) {
                 throw new ServerApiException(BaseCmd.PARAM_ERROR, cause.getMessage());
+            } else if (cause instanceof IllegalArgumentException) {
+                throw new ServerApiException(BaseCmd.PARAM_ERROR, cause.getMessage());
             } else if (cause instanceof PermissionDeniedException) {
                 throw new ServerApiException(BaseCmd.ACCOUNT_ERROR, cause.getMessage());
             } else if (cause instanceof ResourceAllocationException){
             	throw new ServerApiException(BaseCmd.UNSUPPORTED_ACTION_ERROR, cause.getMessage());
+            } else if (cause instanceof ServerApiException) {
+                throw (ServerApiException)cause;
             }
             s_logger.warn("Exception executing method " + methodName + " for command " + cmd.getClass().getSimpleName(), ite);
             throw new ServerApiException(BaseCmd.INTERNAL_ERROR, "Unable to execute method " + methodName + " for command " + cmd.getClass().getSimpleName() + ", internal error in the implementation.");
@@ -149,6 +153,8 @@ public class ApiDispatcher {
             }
             if (cause instanceof InvalidParameterValueException) {
                 throw new ServerApiException(BaseCmd.PARAM_ERROR, cause.getMessage());
+            } else if (cause instanceof IllegalArgumentException) {
+                throw new ServerApiException(BaseCmd.PARAM_ERROR, cause.getMessage());
             } else if (cause instanceof PermissionDeniedException) {
                 throw new ServerApiException(BaseCmd.ACCOUNT_ERROR, cause.getMessage());
             } else if (cause instanceof ServerApiException) {