diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
index 57f734463d8a4bb4bd387d9254e61ccf87fe0e94..fe40de84ebfa5c2d5ca4bec3f994027848833778 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
@@ -41536,7 +41536,7 @@ NULL
 #{ x <- c(10, 20); names(x) <- c('ahoj', 'svete'); y <- c(1,2); z <- choose(x,y); names(z)[[1]] <- 'onlyinz'; names(x) }
 [1] "ahoj"  "svete"
 
-##com.oracle.truffle.r.test.builtins.TestBuiltin_names.testNames#Ignored.ImplementationError#
+##com.oracle.truffle.r.test.builtins.TestBuiltin_names.testNames#
 #{ x <- parse(text='x+y')[[1]]; names(x) <- c('a','b','c'); names(x); }
 [1] "a" "b" "c"
 
@@ -68361,6 +68361,14 @@ integer(0)
 [26] 09 00 00 00 01 2b 00 00 00 02 00 00 00 01 00 04 00 09 00 00 00 01 61 00 00
 [51] 00 02 00 00 00 01 00 04 00 09 00 00 00 01 62 00 00 00 fe
 
+##com.oracle.truffle.r.test.builtins.TestBuiltin_serialize.testserialize#
+#options(keep.source=FALSE); serialize(quote(b + xxxx(yyyy=1)), connection=NULL)
+  [1] 58 0a 00 00 00 02 00 03 04 00 00 02 03 00 00 00 00 06 00 00 00 01 00 04 00
+ [26] 09 00 00 00 01 2b 00 00 00 02 00 00 00 01 00 04 00 09 00 00 00 01 62 00 00
+ [51] 00 02 00 00 00 06 00 00 00 01 00 04 00 09 00 00 00 04 78 78 78 78 00 00 04
+ [76] 02 00 00 00 01 00 04 00 09 00 00 00 04 79 79 79 79 00 00 00 0e 00 00 00 01
+[101] 3f f0 00 00 00 00 00 00 00 00 00 fe 00 00 00 fe
+
 ##com.oracle.truffle.r.test.builtins.TestBuiltin_serialize.testserialize#
 #options(keep.source=FALSE); serialize(quote(f(g)$h.i), connection=NULL)
  [1] 58 0a 00 00 00 02 00 03 04 00 00 02 03 00 00 00 00 06 00 00 00 01 00 04 00
@@ -68583,6 +68591,12 @@ integer(0)
  [1] 58 0a 00 00 00 02 00 03 04 00 00 02 03 00 00 00 00 01 00 04 00 09 00 00 00
 [26] 01 78
 
+##com.oracle.truffle.r.test.builtins.TestBuiltin_serialize.testserialize#
+#options(keep.source=FALSE); serialize(quote(xxxx(yyyy=1)), connection=NULL)
+ [1] 58 0a 00 00 00 02 00 03 04 00 00 02 03 00 00 00 00 06 00 00 00 01 00 04 00
+[26] 09 00 00 00 04 78 78 78 78 00 00 04 02 00 00 00 01 00 04 00 09 00 00 00 04
+[51] 79 79 79 79 00 00 00 0e 00 00 00 01 3f f0 00 00 00 00 00 00 00 00 00 fe
+
 ##com.oracle.truffle.r.test.builtins.TestBuiltin_serialize.testserialize#
 #options(keep.source=FALSE); serialize(quote({ foo(a,b,c) }), connection=NULL)
   [1] 58 0a 00 00 00 02 00 03 04 00 00 02 03 00 00 00 00 06 00 00 00 01 00 04 00
@@ -132293,6 +132307,22 @@ Error in x[["a", "d"]] : subscript out of bounds
 Error in match(x, table, nomatch = 0L) :
   'match' requires vector arguments
 
+##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testLanguageIndex#
+#f <- function(x) x[[1]]; l <- as.pairlist(c('a','b')); f(l); l <- quote(a+b); f(l)
+[1] "a"
+`+`
+
+##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testLanguageIndex#
+#l <- quote(a+b+c); l[[c(2,2)]]; l[[c(2,3)]]; l[[c(2,2)]]; l[[c(3)]]; l <- as.pairlist(c('+','x','c')); l[[2]] <- as.pairlist(c('+','a','b')); l[[c(2,2)]]; l[[c(2,3)]]; l[[c(2,2)]]; l[[c(3)]]
+a
+b
+a
+c
+[1] "a"
+[1] "b"
+[1] "a"
+[1] "c"
+
 ##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testLanguageIndex#
 #{ e <- quote(f(x=a, b)); names(e) }
 [1] ""  "x" ""
@@ -137408,6 +137438,69 @@ Error in `[[.default`(x, "z", exact = TRUE) : subscript out of bounds
 [1] b
 Levels: a b
 
+##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testPairList#
+#l <- as.pairlist(c(1,2,3,4)); l2 <- l; typeof(l); l[[3]] <- 123; typeof(l); l
+[1] "pairlist"
+[1] "pairlist"
+[[1]]
+[1] 1
+
+[[2]]
+[1] 2
+
+[[3]]
+[1] 123
+
+[[4]]
+[1] 4
+
+
+##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testPairList#
+#l <- as.pairlist(c(1,2,3,4)); typeof(l); l[[3]] <- 123; typeof(l); l
+[1] "pairlist"
+[1] "pairlist"
+[[1]]
+[1] 1
+
+[[2]]
+[1] 2
+
+[[3]]
+[1] 123
+
+[[4]]
+[1] 4
+
+
+##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testPairList#
+#l <- pairlist("a","b",1,4,3); typeof(l); typeof(l[[1]]); typeof(l[1]); typeof(l[1:5]); typeof(l[4:5]); l[4:5]
+[1] "pairlist"
+[1] "character"
+[1] "list"
+[1] "list"
+[1] "list"
+[[1]]
+[1] 4
+
+[[2]]
+[1] 3
+
+
+##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testPairList#
+#l <- quote(a("b",1,4,3)); typeof(l); typeof(l[[1]]); typeof(l[1]); typeof(l[1:5]); typeof(l[4:5]); l[4:5]
+[1] "language"
+[1] "symbol"
+[1] "language"
+[1] "language"
+[1] "language"
+4(3)
+
+##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testPairList#
+#x <- as.pairlist(list(7,42)); x[[1]] <- list(); typeof(x); x$foo <- 123; typeof(x); x[1] <- list(1); typeof(x)
+[1] "pairlist"
+[1] "pairlist"
+[1] "list"
+
 ##com.oracle.truffle.r.test.library.base.TestSimpleVectors.testPrint#
 #{ mp<-getOption("max.print"); options(max.print=3); x<-c(1,2,3,4,5); attr(x, "foo")<-"foo"; print(x); options(max.print=mp) }
 [1] 1 2 3
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_names.java b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_names.java
index 147f9137f9ae7786841967d1d25194d966a49e6a..39cc1c3415710f3779c56175291c2df9c12192bf 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_names.java
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_names.java
@@ -206,8 +206,7 @@ public class TestBuiltin_names extends TestBase {
         assertEval("{ y<-c(d=\"e\"); attr(y, \"foo\")<-\"foo\"; x<-c(42); names(x)<-y; attributes(names(x)) }");
         assertEval("{ x <- c(10, 20); names(x) <- c('ahoj', 'svete'); y <- c(1,2); z <- choose(x,y); names(z)[[1]] <- 'onlyinz'; names(x) }");
         assertEval("{ e <- new.env(); names(e) <- c('a'); }");
-        // FIXME: set names on language does not set the first name
-        assertEval(Ignored.ImplementationError, "{ x <- parse(text='x+y')[[1]]; names(x) <- c('a','b','c'); names(x); }");
+        assertEval("{ x <- parse(text='x+y')[[1]]; names(x) <- c('a','b','c'); names(x); }");
         assertEval("names(pairlist(a=3, b=4))");
         assertEval("names(pairlist(1,2,3))");
         assertEval("names(pairlist(a=1,2,q=3))");
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_serialize.java b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_serialize.java
index 07b12af333d27fd0cff34d59e59c3c151129a8fd..657af5b35ceb6d06428550efc3877f40aef34d45 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_serialize.java
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_serialize.java
@@ -72,6 +72,8 @@ public class TestBuiltin_serialize extends TestBase {
         assertEval("options(keep.source=FALSE); serialize(quote(if ({a}) {b} else {c}), connection=NULL)");
         assertEval("options(keep.source=FALSE); serialize(quote(while (a) b), connection=NULL)");
         assertEval("options(keep.source=FALSE); serialize(quote(repeat {b; if (c) next else break}), connection=NULL)");
+        assertEval("options(keep.source=FALSE); serialize(quote(xxxx(yyyy=1)), connection=NULL)");
+        assertEval("options(keep.source=FALSE); serialize(quote(b + xxxx(yyyy=1)), connection=NULL)");
         assertEval("options(keep.source=FALSE); serialize(quote(if (a * 2 < 199) b + foo(x,y,foo=z+1,bar=)), connection=NULL)");
         assertEval("options(keep.source=FALSE); serialize(quote(\"bar\"), connection=NULL)");
         assertEval("options(keep.source=FALSE); serialize(quote('baz'), connection=NULL)");
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestSimpleVectors.java b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestSimpleVectors.java
index c5c3df31e1d5c3a1e07cf9633c98f7d8dbc99195..57a1f724bdd9bd8c51e08587aeadffaacece0456 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestSimpleVectors.java
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestSimpleVectors.java
@@ -712,6 +712,18 @@ public class TestSimpleVectors extends TestBase {
         assertEval("{ x<-quote(function(x, y=7) 42); x[[2]] }");
 
         assertEval("{ f<-quote(function(x=42) x); f[[2]]$x<-7; eval(f)() }");
+
+        assertEval("f <- function(x) x[[1]]; l <- as.pairlist(c('a','b')); f(l); l <- quote(a+b); f(l)");
+        assertEval("l <- quote(a+b+c); l[[c(2,2)]]; l[[c(2,3)]]; l[[c(2,2)]]; l[[c(3)]]; l <- as.pairlist(c('+','x','c')); l[[2]] <- as.pairlist(c('+','a','b')); l[[c(2,2)]]; l[[c(2,3)]]; l[[c(2,2)]]; l[[c(3)]]");
+    }
+
+    @Test
+    public void testPairList() {
+        assertEval("l <- as.pairlist(c(1,2,3,4)); typeof(l); l[[3]] <- 123; typeof(l); l");
+        assertEval("l <- as.pairlist(c(1,2,3,4)); l2 <- l; typeof(l); l[[3]] <- 123; typeof(l); l");
+        assertEval("x <- as.pairlist(list(7,42)); x[[1]] <- list(); typeof(x); x$foo <- 123; typeof(x); x[1] <- list(1); typeof(x)");
+        assertEval("l <- quote(a(\"b\",1,4,3)); typeof(l); typeof(l[[1]]); typeof(l[1]); typeof(l[1:5]); typeof(l[4:5]); l[4:5]");
+        assertEval("l <- pairlist(\"a\",\"b\",1,4,3); typeof(l); typeof(l[[1]]); typeof(l[1]); typeof(l[1:5]); typeof(l[4:5]); l[4:5]");
     }
 
     @Test