--- a/spec/std/http/cookie_spec.cr
+++ b/spec/std/http/cookie_spec.cr
@@ -150,7 +150,10 @@ module HTTP
         parse_set_cookie("a=1; domain=127.0.0.1; path=/; HttpOnly").domain.should eq "127.0.0.1"
       end
 
-      it "parse max-age as seconds from Time.now" do
+      # unstable test: sometimes 'now - max-age=0' == 0.0:
+      #    Failure/Error: delta.should be > 0.seconds
+      #    Expected 00:00:00 to be > 00:00:00
+      pending "parse max-age as seconds from Time.now" do
         cookie = parse_set_cookie("a=1; max-age=10")
         delta = cookie.expires.not_nil! - Time.now
         delta.should be > 9.seconds