diff --git a/configure.ac b/configure.ac
index 233901c..66ce71a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -94,7 +94,7 @@ if test "x$ob_cv_with_ssl" != xno; then
     sav_LDFLAGS=$LDFLAGS
     LDFLAGS="$LDFLAGS $SSL_LDFLAGS"
     AC_CHECK_LIB(dl, dlopen, [LIBDL=-ldl])
-    AC_CHECK_LIB(crypto, CRYPTO_lock, [LIBCRYPTO=-lcrypto])
+    AC_CHECK_LIB(crypto, X509_cmp, [LIBCRYPTO=-lcrypto])
     AC_CHECK_LIB(ssl, SSL_connect,
                  [SSL_LIBS="-lssl $LIBCRYPTO $LIBDL" have_ssl_paths=yes])
     LDFLAGS=$sav_LDFLAGS