fixes signal handling
fixes signal handling

Ignore-this: d818458db367ec44efd78871f763eae1

darcs-hash:20100705071520-c41ad-b0c46be500d2719cb7040dee2db1fecbe7948516

c-cube/lwt,c-cube/lwt,rgrinberg/lwt,mfp/lwt,rgrinberg/lwt,ocsigen/lwt,janestreet/lwt-async,ocsigen/lwt,rgrinberg/lwt,gfxmonk/lwt,mirage/lwt,rneswold/lwt,fdopen/lwt,c-cube/lwt,gfxmonk/lwt,fdopen/lwt,ocsigen/lwt,mirage/lwt,rgrinberg/lwt,rneswold/lwt,mfp/lwt,janestreet/lwt-async,rneswold/lwt