--- a/jdk/src/java.base/unix/classes/sun/net/dns/ResolverConfigurationImpl.java	Tue Apr 21 14:23:58 2015 +0100
+++ b/jdk/src/java.base/unix/classes/sun/net/dns/ResolverConfigurationImpl.java	Tue Apr 21 14:36:57 2015 +0100
@@ -85,6 +85,15 @@
                     if (val.charAt(0) == '#' || val.charAt(0) == ';') {
                         break;
                     }
+                    if ("nameserver".equals(keyword)) {
+                        if (val.indexOf(':') >= 0 &&
+                            val.indexOf('.') < 0 && // skip for IPv4 literals with port
+                            val.indexOf('[') < 0 &&
+                            val.indexOf(']') < 0 ) {
+                            // IPv6 literal, in non-BSD-style.
+                            val = "[" + val + "]";
+                        }
+                    }
                     ll.add(val);
                     if (--maxvalues == 0) {
                         break;

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/javax/naming/dns/IPv6NameserverPlatformParsingTest.java	Tue Apr 21 14:36:57 2015 +0100
@@ -0,0 +1,81 @@
+import java.lang.reflect.Field;
+import java.util.Hashtable;
+
+import javax.naming.Context;
+import javax.naming.NamingException;
+import javax.naming.spi.NamingManager;
+
+import com.sun.jndi.dns.DnsContext;
+
+/**
+ * @test
+ * @bug 6991580
+ * @summary IPv6 Nameservers in resolv.conf throws NumberFormatException
+ * @run main/manual IPv6NameserverPlatformParsingTest
+ *
+ * In order to run this test be sure to place, for example, the following
+ * snippet into your platform's {@code /etc/resolv.conf}:
+ * <pre>
+ * nameserver 127.0.0.1
+ * nameserver 2001:4860:4860::8888
+ * nameserver [::1]:5353
+ * nameserver 127.0.0.1:5353
+ * </pre>
+ *
+ * Then, run this test as manual jtreg test.
+ *
+ * @author Severin Gehwolf
+ *
+ */
+public class IPv6NameserverPlatformParsingTest {
+
+    private static boolean foundIPv6 = false;
+
+    public static void main(String[] args) {
+        Hashtable<String, String> env = new Hashtable<>();
+        env.put(Context.INITIAL_CONTEXT_FACTORY, com.sun.jndi.dns.DnsContextFactory.class.getName());
+
+        String[] servers;
+        try {
+            Context ctx = NamingManager.getInitialContext(env);
+            if (!com.sun.jndi.dns.DnsContextFactory.platformServersAvailable()) {
+                throw new RuntimeException("FAIL: no platform servers available, test does not make sense");
+            }
+            DnsContext context = (DnsContext)ctx;
+            servers = getServersFromContext(context);
+        } catch (NamingException e) {
+            throw new RuntimeException(e);
+        }
+        for (String server: servers) {
+            System.out.println("DEBUG: 'nameserver = " + server + "'");
+            if (server.indexOf(':') >= 0 && server.indexOf('.') < 0) {
+                System.out.println("DEBUG: ==> Found IPv6 address in servers list: " + server);
+                foundIPv6 = true;
+            }
+        }
+        try {
+            new com.sun.jndi.dns.DnsClient(servers, 100, 1);
+        } catch (NumberFormatException e) {
+            throw new RuntimeException("FAIL: Tried to parse non-[]-encapsulated IPv6 address.", e);
+        } catch (Exception e) {
+            throw new RuntimeException("ERROR: Something unexpected happened.");
+        }
+        if (!foundIPv6) {
+            // This is a manual test, since it requires changing /etc/resolv.conf on Linux/Unix
+            // platforms. See comment as to how to run this test.
+            throw new RuntimeException("ERROR: No IPv6 address returned from platform.");
+        }
+        System.out.println("PASS: Found IPv6 address and DnsClient parsed it correctly.");
+    }
+
+    private static String[] getServersFromContext(DnsContext context) {
+        try {
+            Field serversField = DnsContext.class.getDeclaredField("servers");
+            serversField.setAccessible(true);
+            return (String[])serversField.get(context);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+}