After i remove a workfow event in the admin interface

1. ezadminurl/ workflow/workflowlist/2
2. => remove selected item

their were some static warnings in the strict.log

Non-static method eZTrigger::removeTriggerForWorkflow() should not be called statically, assuming $this from incompatible context in /.../kernel/workflow/workflowlist.php on line 76

Non-static method eZWorkflow::setIsEnabled() should not be called statically, assuming $this from incompatible context in /.../kernel/workflow/workflowlist.php on line 79