diff --git a/lib/less/tree/mixin.js b/lib/less/tree/mixin.js
index 17a4e672..868d3859 100644
--- a/lib/less/tree/mixin.js
+++ b/lib/less/tree/mixin.js
@@ -97,7 +97,7 @@ tree.mixin.Definition.prototype = {
     rulesets:  function ()     { return this.parent.rulesets.apply(this) },
 
     evalParams: function (env, args, evaldArguments) {
-        var frame = new(tree.Ruleset)(null, []), varargs, arg, params = this.params.slice(0), i, j, val, name, isNamedFound;
+        var frame = new(tree.Ruleset)(null, []), varargs, arg, params = this.params.slice(0), i, j, val, name, isNamedFound, argIndex;
         
         if (args) {
             args = args.slice(0);
@@ -125,16 +125,16 @@ tree.mixin.Definition.prototype = {
                 }
             }
         }
-
+        argIndex = 0;
         for (i = 0; i < params.length; i++) {
             if (evaldArguments[i]) continue;
             
-            arg = args && args[i]
-			
+            arg = args && args[argIndex];
+
             if (name = params[i].name) {
                 if (params[i].variadic && args) {
                     varargs = [];
-                    for (j = i; j < args.length; j++) {
+                    for (j = argIndex; j < args.length; j++) {
                         varargs.push(args[j].value.eval(env));
                     }
                     frame.rules.unshift(new(tree.Rule)(name, new(tree.Expression)(varargs).eval(env)));
@@ -148,10 +148,11 @@ tree.mixin.Definition.prototype = {
             }
             
             if (params[i].variadic && args) {
-                for (j = i; j < args.length; j++) {
+                for (j = argIndex; j < args.length; j++) {
                     evaldArguments[j] = args[j].value.eval(env);
                 }
             }
+            argIndex++;
         }
 
         return frame;
diff --git a/test/css/mixins-args.css b/test/css/mixins-args.css
index 365d5fc9..91104aca 100644
--- a/test/css/mixins-args.css
+++ b/test/css/mixins-args.css
@@ -89,3 +89,7 @@ body {
   one: r, s;
   two: t;
 }
+#named-conflict {
+  four: a, 11, 12, 13;
+  four: a, 21, 22, 23;
+}
diff --git a/test/less/mixins-args.less b/test/less/mixins-args.less
index 76ba2623..f71bdce1 100644
--- a/test/less/mixins-args.less
+++ b/test/less/mixins-args.less
@@ -137,18 +137,31 @@ body {
 
 .mixin-takes-two(@a; @b) {
     one: @a;
-	two: @b;
+    two: @b;
 }
 
 .comma-vs-semi-colon {
     .mixin-takes-two(@a : a; @b : b, c);
-	.mixin-takes-two(@a : d, e; @b : f);
-	.mixin-takes-one(@a: g);
-	.mixin-takes-one(@a : h;);
-	.mixin-takes-one(i);
-	.mixin-takes-one(j;);
-	.mixin-takes-two(k, l);
-	.mixin-takes-one(m, n;);
-	.mixin-takes-two(o, p; q);
-	.mixin-takes-two(r, s; t;);
+    .mixin-takes-two(@a : d, e; @b : f);
+    .mixin-takes-one(@a: g);
+    .mixin-takes-one(@a : h;);
+    .mixin-takes-one(i);
+    .mixin-takes-one(j;);
+    .mixin-takes-two(k, l);
+    .mixin-takes-one(m, n;);
+    .mixin-takes-two(o, p; q);
+    .mixin-takes-two(r, s; t;);
 }
+
+.mixin-conflict(@a:defA, @b:defB, @c:defC) {
+  three: @a, @b, @c;
+}
+
+.mixin-conflict(@a:defA, @b:defB, @c:defC, @d:defD) {
+  four: @a, @b, @c, @d;
+}
+
+#named-conflict {
+  .mixin-conflict(11, 12, 13, @a:a);
+  .mixin-conflict(@a:a, 21, 22, 23);
+}
\ No newline at end of file