Here is the patch you can try out. Please give me your feedback. http://linux.junsun.net/realtime-linux Note a couple of things: . it is against 2.4.10 . to apply it cleanly you need to check oss CVS tree on 10/30. See readme. . you can only run it on a board that is configured with CONFIG_NEW_IRQ. An updated patch, probably against 2.4.14, will be made soon - hopefully. :-) Jun