diff --git a/configure.in b/configure.in
index 2123e74a17..58b126618a 100644
--- a/configure.in
+++ b/configure.in
@@ -1428,7 +1428,7 @@ dnl Check whether we need to define sys_nerr locally
 AC_CHECK_DECLS([sys_nerr], [], [], [$ac_includes_default
 @%:@include <errno.h>])
 
-AC_CHECK_LIB(crypt, crypt)      # GNU/Linux
+AC_CHECK_LIB(crypt, crypt)      # glibc (GNU/Linux, GNU/Hurd, GNU/kFreeBSD)
 AC_CHECK_LIB(dl, dlopen)	# Dynamic linking for SunOS/Solaris and SYSV
 AC_CHECK_LIB(dld, shl_load)	# Dynamic linking for HP-UX
 AC_CHECK_LIB(rt, clock_gettime)	# GNU/Linux