diff --git a/configure.in b/configure.in
index 4f28a4a..06a5451 100644
--- a/configure.in
+++ b/configure.in
@@ -219,6 +219,7 @@ AC_INIT(c/scheme48vm.c)
      AC_CHECK_LIB(gen, main)
      AC_CHECK_LIB(socket, main)
      AC_CHECK_LIB(sun, getpwnam)
+     AC_CHECK_LIB(c, crypt, [true], AC_CHECK_LIB(crypt, crypt))
      dnl Solaris 2.3 seems to need -lelf for nlist().  (tnx Bryan O'Sullivan)
      AC_CHECK_LIB(elf, main)
      S48_POSIX_LIBC
@@ -226,6 +227,7 @@ AC_INIT(c/scheme48vm.c)
      AC_RETSIGTYPE
      AC_CHECK_HEADERS(libgen.h sys/timeb.h posix/time.h sys/select.h nlist.h)
      AC_CHECK_HEADERS(sys/un.h)
+     AC_CHECK_HEADERS(crypt.h)	
      AC_CHECK_FUNCS(gettimeofday ftime nlist select setitimer sigaction)
      AC_CHECK_FUNC(dlopen, AC_DEFINE(HAVE_DLOPEN),
 			   AC_CHECK_FUNC(nlist, [LIBOBJS="$LIBOBJS c/fake/libdl1.c],