diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/RRuntime.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/RRuntime.java
index 946ddaea7cfaba4cd64baf7d6ecc567425f10f84..952fd55f57d58ac2171a5fc353eb876fdcc93da0 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/RRuntime.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/RRuntime.java
@@ -450,7 +450,8 @@ public class RRuntime {
         // FIXME use R rules
         int result;
         try {
-            result = Integer.decode(Utils.trimLeadingZeros(s));  // decode supports hex constants
+            result = Integer.decode(Utils.trimLeadingZeros(s.trim()));  // decode supports hex
+                                                                        // constants
         } catch (NumberFormatException e) {
             if (exceptionOnFail) {
                 throw e;
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 32b76d9697053cbe4b8b7c36d045e18977eb89fe..f2163da30998c44ffd6db0eba356097af5a4ffbd 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
@@ -7377,7 +7377,7 @@ NAs introduced by coercion to integer range
 [551]  4  4  2  4  4  4  4  3  2  3  3  2 NA  3  4  4  3  3  4  4  4  1  4  4  4
 [576]  4  4  4  4  2  4  2  3  4  1  3  1 NA  4  1  2  2  1  4  3  3  4  1  1  3
 
-##com.oracle.truffle.r.test.builtins.TestBuiltin_asinteger.testasinteger2#Ignored.ImplementationError#
+##com.oracle.truffle.r.test.builtins.TestBuiltin_asinteger.testasinteger2#
 #argv <- list(c('   33', '   34', '   35', '   36', '   37', '   38', '   18', '   19', '   20', '   21', '   22', '   23', '   36', '   37', '   38', '   39'));as.integer(argv[[1]]);
  [1] 33 34 35 36 37 38 18 19 20 21 22 23 36 37 38 39
 
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_asinteger.java b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_asinteger.java
index b4a10d805407ed648820074951978e381ca909b5..cfcf46fc1adf9ca4235b8b7e7cb3bd3a104836e5 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_asinteger.java
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/builtins/TestBuiltin_asinteger.java
@@ -34,9 +34,7 @@ public class TestBuiltin_asinteger extends TestBase {
 
     @Test
     public void testasinteger2() {
-        // FIXME according to docs a leading whitespace should be accepted
-        assertEval(Ignored.ImplementationError,
-                        "argv <- list(c('   33', '   34', '   35', '   36', '   37', '   38', '   18', '   19', '   20', '   21', '   22', '   23', '   36', '   37', '   38', '   39'));as.integer(argv[[1]]);");
+        assertEval("argv <- list(c('   33', '   34', '   35', '   36', '   37', '   38', '   18', '   19', '   20', '   21', '   22', '   23', '   36', '   37', '   38', '   39'));as.integer(argv[[1]]);");
     }
 
     @Test