diff --git a/lib/ace/mode/scala_highlight_rules.js b/lib/ace/mode/scala_highlight_rules.js
index 443e6350..c39962db 100644
--- a/lib/ace/mode/scala_highlight_rules.js
+++ b/lib/ace/mode/scala_highlight_rules.js
@@ -80,7 +80,7 @@ var ScalaHighlightRules = function() {
                 next : "tstring"
             }, {
                 token : "string",
-                regex : '"',
+                regex : '"(?=.)', // " strings can't span multiple lines
                 next : "string"
             }, {
                 token : "symbol.constant", // single line
@@ -146,6 +146,10 @@ var ScalaHighlightRules = function() {
                 merge : true,
                 regex : '"',
                 next : "start"
+            }, {
+                token : "string.invalid",
+                regex : '[^"\\\\]*$',
+                next : "start"
             }, {
                 token : "string",
                 regex : '[^"\\\\]+',