diff --git a/.travis.yml b/.travis.yml
index ac8d81295dc4308f8725b1b7d96187f11f1f9331..82fada2c7666806118a263786c1d081473791e30 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -83,7 +83,7 @@ before_script:
     - cd ..
 
 script:
-    - if expr "$CONFIG_OPTS" : "--unified"; then
+    - if echo "$CONFIG_OPTS" | grep "--unified" >/dev/null; then
           cd _build;
       else
           cd _srcdist;