--- Imakefile.orig	Fri May 28 15:59:18 2010
+++ Imakefile	Fri May 28 15:59:46 2010
@@ -124,7 +124,7 @@ EXTRA_LIBRARIES = -lnsl -lposix4
        SLEEPDEF = -DHAVE_USLEEP=1
 #endif
 #endif
-#if defined(FreeBSDArchitecture) || defined(NetBSDArchitecture) || defined(i386BsdArchitecture)
+#if defined(FreeBSDArchitecture) || defined(NetBSDArchitecture) || defined(OpenBSDArchitecture) || defined(i386BsdArchitecture)
        SLEEPDEF = -DHAVE_USLEEP=1
 #endif
 #ifdef LinuxArchitecture
