Index: coffee.module
===================================================================
--- coffee.module	(revision 622)
+++ coffee.module	(working copy)
@@ -59,12 +59,13 @@
   // Or it should handle the basic functionality (redirecting to paths).
   $command_trigger = ':';
 
+  $result = array();
   // Invoke all implementations of hook_coffee_command() on command_trigger.
   if (strstr(urldecode($input), $command_trigger)) {
     // Execute command, invode hook_coffee.
     foreach (module_implements('coffee_command') as $module) {
       $op = str_ireplace($command_trigger, '', $input);
-      $result = module_invoke($module, 'coffee_command', $op);
+      $result += (array)module_invoke($module, 'coffee_command', $op);
     }
   }
   else {