diff --git a/lib/plugins/conditionalHandler.js b/lib/plugins/conditionalHandler.js
index 7ddf55c1b..f2108c442 100644
--- a/lib/plugins/conditionalHandler.js
+++ b/lib/plugins/conditionalHandler.js
@@ -126,7 +126,7 @@ function conditionalHandler(candidates) {
             reqCandidates = candidates.filter(function filter(candidate) {
                 var neg = new Negotiator({
                     headers: {
-                        accept: candidate.contentType.join(', ')
+                        accept: (candidate.contentType) ? candidate.contentType.join(', ') : ''
                     }
                 });
                 var tmp = neg.preferredMediaType(contentTypes);