Recently I mentioned the topic of lying in order to surprise someone and quoted a contemporary authority that it is forbidden. I received two emails. One person said "that's crazzzzzyyyy" and asked if there are other opinions [knowing the person well I can assure you that no disrespect was meant..]. Another mentioned that white lies are permitted according to halacha.
So "by chance" ['מקרה אותיות רק מה] I was learning the sefer Yashiv Yitzchak [written by one of the most prolific authors of our generation, Rabbi Yitzchak Shechter a Dayan in Netanya, the end of chelek aleph - the first of maybe 35 volumes and he's still going!] and saw a lengthy discussion about the paramaters of the prohibition of lying and I direct you there. I then saw the Yalkut Yosef [kibbud av vi-eim page 487]. I direct you there even if you happen to be ashkenazi. Ashkenazim learn Talmud Bavli and Rambam so they may also learn Yalkut Yosef.
Bottom line: There are opinions that lying is only forbidden if it will cause harm to someone else but white lies are permitted [at least biblically]. According to this, lying in order to surprise someone should be permitted. I would compare it to telling the choson that his kalla is beautiful and righteous [כלה נאה וחסודה] despite the fact that she may not be so. Both achieve the goal of making people happy.
But I am not paskening - just presenting the sources.
See also שו"ת ציץ אליעזר חט"ו סי"ב and this article by a GOOOD friend.