Note this isn't with cordova, it's just running the page in the browser.

From the exception stack trace it looked like cordova issue - iOS browser is opening some URL and it fails. But after one more look the problem is in WebUtils.getLocalhostInetAddress:530 - it calls java.net.InetAddress.getLocalHost() which fails on your Mac for some reason. This should be unrelated to migration to PhoneGap 3.0 as it is a JDK call. Leaving to Honza for evaluation as he wrote WebUtils.getLocalhostInetAddress method.

I guess, that it is
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7180557

I asked in the JDK bug for a fix on their side.

Let's look also for a possibility of a workaround.

Why would John have this problem and nobody else? PetrJ is using Mac too.

No idea why that happens just on john's Mac and no idea how hostnames are resolved on Macs. We were not able to reproduce on none of macs here in Prague office. Maybe it's related to jumping from Oracle network (and Oracle DNS services) to home mode (just local DNS resolve). I can reproduce something similar on my Linux but only if i manually edit /etc/hosts and change:
> ::1             localhost ipv6-localhost ipv6-loopback ovrabec.netbeans
to
> ::1             localhost ipv6-localhost ipv6-loopback
Than my machine cannot resolve ovrabec.netbeans either. I checked some of my college's Mac laptops and their config file is almost empty but maybe it could help john to add/modify /etc/hosts:
::1             localhost ipv6-localhost ipv6-loopback jjullion-mac

Content of my /etc/hosts:

##
127.0.0.1       localhost
255.255.255.255 broadcasthost
::1             localhost
fe80::1%lo0     localhost


Adding jjullion-mac to ::1 list solved the problem. How can we intercept these errors and send people to a wiki or give them some help in an error dialog on how to fix it?

I suppose this should do, reassigning to the author of WebUtils

# This patch file was generated by NetBeans IDE
# Following Index: paths are relative to: D:\hg\core-main
# This patch can be applied using context Tools: Patch action on respective folder.
# It uses platform neutral UTF-8 encoding and \n newlines.
# Above lines and this line are ignored by the patching process.
Index: web.common/src/org/netbeans/modules/web/common/api/WebUtils.java
--- web.common/src/org/netbeans/modules/web/common/api/WebUtils.java Base (BASE)
+++ web.common/src/org/netbeans/modules/web/common/api/WebUtils.java Locally Modified (Based On LOCAL)
@@ -52,6 +52,7 @@
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
+import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Enumeration;
 import java.util.List;
@@ -547,6 +548,9 @@
                 }
             }
             return localHost;
+        } catch ( UnknownHostException uhE) {
+            Logger.getLogger( WebUtils.class.getName() ).log( Level.WARNING, "Cannot resolve local host address, please check your network configuration.", uhE);
+            throw new IllegalStateException(uhE);
         } catch (Exception ex) {
             throw new IllegalStateException(ex);
         }

The JDK bug 7180557 is fixed in JDK 8 (build 113). I have also modified the message of this exception to be more informative => I am closing this issue as fixed.

Modified file: https://hg.netbeans.org/web-main/rev/c6fa61c002c5